Weed eater engine conversion

[Ward]

Im currently trying to design a way to drive my 12' pirogue with a weed eater engine i recently picked up for free. I know it probably sounds dumb, but I believe it can work. However, I don't know how to find out what size/type/pitch prop I will need. I am hoping to have direct drive for simplicity. I don't know the exact specs on the engine yet, but most weed eaters are around 30cc. I would estimate its power at 1HP at best. Any information is greatly appreciated, and let me know if you need more information on the engine/boat.

[Jeff]

While I was searching for a site that I found a long time ago but couldn't locate tonight, I stumbled upon http://www.go-devil.com/ which might lead to some ideas, though their engines start at a 5.5 hp honda, so I guess they're more lawn mower engines then weed eater engines

There are lots of threads in rec.boats.buliding (http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=weed+eater+group%3Arec.boats.building&btnG=Google+Search&meta=group%3Drec.boats.building) from the last few years talking about projects similar to yours (you can also search rec.boats.building through google groups (http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=weedeater+group%3Arec.boats.building&btnG=Google+Search&meta=group%3Drec.boats.building)). But I couldn't find many specific answers or sources for what you're looking for... mostly posts as people began their conversion projects.

Large RC model boats commonly have the size engine you're talking about though. Most often they're inboards but I've also seen them mated to miniature RC IO drives which was neat for a model. The converted weed eater engines go for around $200-250 as a kit for RC boatbuilders. Others I know have converted weed eater engines themselves for RC boats, but I'm not sure how much assortment of miniature weed eater props there is...

Isn't the noise going to drive you mad?

[Ward]

The engine is really not that loud, but anything beats paddling :P

It appears that this is the best way to mount the engine. The pull start, handle, and throttle trigger are all in great locations. the handle could be used as a tiller. I do see a couple of problems however. First, this is rotated 90 degrees counter-clockwise from the way you would hold it as a weed eater, which puts the fuel tank filler cap facing forward. Not a big deal, I could always just mount a new tank. This one is part of the handle, so I can't just remove it and rotate it. Another possible problem I see is the location of the spark plug. It looks like its just asking to get drenched, and short out. I'm thinking some sort of small shield to surround it should be sufficient, as this will never see high speeds. Other than that, the only real problems left are figuring out how to mount it to a transomless pirogue, as well as finding/making a suitable prop.

I have thought of one other thing, however. most weed eaters are designed so that the engine can be easily removed from the shaft, in order to change from say a trimmer, to an edger. An edging attachment has a gearbox at the bottom, at a right angle to the shaft, with some gear reduction. I may see if I can find one of these, and see what type of gear reduction it has. I'm thinking it might just be enough to be able to use a small trolling motor prop.

[badges65]

HI,
already made one my son found a 1.5 HP evinrude outboard on the sand bank opposite the house and as the top half was completely corroded away but bottom end was okay fitted a weedeater top to it with a centrafugal clutch and now have a outboard which will even drive the 3.5M IVB ..!!!!??
don

[gonzo]

There are plenty of trolling motors with bad electrical motors to be had for free. Seems like the ideal setup to add a gas motor to. Check your local marinas or shops. I know we've thrown many in the trash since they are not worth fixing.

[Ward]

How could I use a trolling motor? I I thought the electric motor was in the 'pod' at the bottom of the motor. Badges65, do you have any pics of the motor? I thought about using an old intermediate and lower unit from an outboard, but I don't know how I could attach the weed eater motor to it, and have it drive the lower unit. Also, would it have to have a clutch on it? I thought the lower unit would give your forward, neutral, and reverse.

[gonzo]

I thought it would be possible to hook up the flexible shaft to the electric lower unit.

[badges65]

Hi Ward,
will get some pics in a couple of days and also of another version of the use of a weedeater a 12V generator!!???
The only problem was marrying the output of the weedeater drive to the shaft of the outboard leg, but its a little beaut as just give it the tit and she drives swell no tit and in neutral. turn the whole motor 180 degs as in the normal outboard version for reverse.
don

[Ward]

Do you guys think I could simply use a trolling motor prop? I looked at a few at wal-mart, and the smallest one they have is about 6" in diamter. the pitch wasn't listed on the box. I'm thinking the little weed eater motor wouldnt have enough torque to swing such a large prop without some sort of gear reduction. I wish it would work though, because it would bolt right up to the outpout shaft for the weed eater.

[badges65]

Hi Ward,
here are the pics of weedeater conversions..

[badges65]

HI all,
sorry looks like it will only take one file att..
will have to post 2 more times..
don

[badges65]

last one
don

[Ward]

Who, the outboard looks awesome! It looks like it came from the factory that way. Thanks for the pics :)

[badges65]

Hi Ward,
forgot to mention that it is swinging a 7 inch 3 blade prop.
don

[hearsejr]

I would be interested in any info you guys might be willing to share on the weed eater/ out board idea.
thanks,
Bill

[wet-foot]

A few things to consider, Use any prop that will bolt to the shaft. Use water proof grease in the flex shaft housing. Try convert the handle into the transom bracket. The handles are usually adjustable to slide up and down the shaft ....... keep this option as the biggest concern you will have once you make it work will be prop depth. If the prop runs too deep you will get a lot of cavitation ( no speed ) ..... shallow is what you want. You should be able to adjust the vertical height with the handle and the prop angle by tilting the engine. Also convert the exhaust with a tube that reaches under water ....... now that's quiet!!!!!! The only thing you can't really fix is the fact weedeater motors are meant to run at full throttle like chainsaws ...... but it will still work, just a little hard to control your speed. Good Luck - let us know how you make out.

[Guest]

Hey Tex! It isn't dumb. It's a great idea and it works. I had one but some miserable, oxygen-thieving waste of space needed it more than me. Apparently! I can't tell you anything about it of use to you other than it was direct drive. The shaft had been cut down to about two and a half feet and it was a Ryobi Scorpion which as you say is 30cc. It was so ingenious I fell in love with it even though I know nothing about motors. In fact I was surfing the net looking for something on my Evinrude Junior which I also know nothing about when I hit this site and decided to give it a go. I got a real kick when I saw your name cause we must be cousins. My name is Joe Ward but I ain't in Texas. I'm in Gladstone, Queensland, Australia. When I read your request for info on a weedeater outboard I felt I had to at least let you know you ain't dumb and in all likelihood are probably a genious. I thought I'd had the only one in existence and to find out there's another Ward out there in Texas who's trying to make one made me smile. If this ain't a billion to one shot coincidence then there ain't no such thing.Take care dude and don't give up. It works.
Cousin Joe.

[fourwheelin415]

hi me and my freind put together a weed eater boat motor with a idc weed eater motor and and a homlite shaft and the rod on the in side we only had to modify it slitly. Then we used a prop off a eska trowling motor and we constently said that it was going to gether to easy and when we got done and started the motor we relized that it was runing backwards. So if any one knows where i can get a counter clock wise prop cheap let me know.

[TopSpin80]

I would definately not go with a flex shaft. I have r/c weedeater boats and flex shaft's don't work. There is a huge torque load on a marine engine at all times no matter the hp. The flex shaft is designed for a weedeater application running in free air and only minimal torque, it will break all the time in a marine application.

[SailDesign]

One of the early Herreshoff steam launches had a "bent" (his words) prop shaft. No word on whether it was successful or not, apart from the fact that no-one does it any more...

[fourwheelin415]

The weed eater/ out bouat me and my freind built works great we didnt finish the transome mount but it does push us along great in the boat we built. Its only an eight footer but it pretty good for our first one. Where going to start building a 10 footer the winter. Where going to put the weed eaters "3" in the middle of the boat witha straight shaft running out the bottom of the boat with the rudders on the back. We are just builting jon boats so far. But there my design and no one is helping us so i think thats good for a couple of 15 year olds. And that flez shaft works great for us so were going to stick with it and build a couple more motors to put in our new boat.

Cody

[gonzo]

Where in Wisconsin are you? I teach boatbuilding in Milwaukee. Call me if you need any help.

[SailDesign]

Gonzo - you're a good man. Thanks.

[fourwheelin415]

I was woundering if any one gould hook me up with a stearing unit and cable. I have a very tight buget and would like to make my boat a inboard. The only problems that ive been having is the stearing. I tryed cables but it didnt work at all. The rudder bairly move left and right. Olso i was wondering if any one had any extra smaller props lying around.

Thanks, cody

[gonzo]

Pulleys work if properly designed. I'll post a schematic tomorrow. Can you use a beat up propeller?

[fourwheelin415]

SURE, But ive slitly altered my plans. I am now going to make a few changes to my boat. I am going to combine it with a lawnmower and other scrap metal to make it a anphibious vehical, instead of having to push it on a dolly i made. And because my dad wants me to get rid of the mower. Ive got it planned out and have almost all of the nessesitys exept the scrape metal, which ill get this summer when i have some money. thanks. Ill send you some of my plans if i can get my scanner to work.


Cody

[Joshua C.]

Hey man,
Just built a boat around high performance weed wacker engines. uses two 25.4cc 2cycle gas engines(3.5 HP each) and mini jet drives (I ould only get 1/3 throttle and about 12 mph out of my old canoe before air was forced into the jets and they would cavitate, wrong hull shape). MANY other mods to be put on the web later as I am 4 days away from the maiden voyage/christaining.

HINT to use an el cheapo gas engine you will need a clutched model (more torque ) and you will need to mount your engine in the boat through the hull and use a "stuffing tube filled with grease" or figure out a way to seal the shaft or the rotating flex shaft will draw water up the pipe and all over you and your boat/engine. So far as the prop is concerned I started out using a 2.9" RC boat prop (I think it was called a prather 275) and with a single 30cc john deere with a clutch I was able to go faster than paddling with 2 people and gear in the boat!!

Belive me I have been wasting $ on this project for 3 years and KNOW what I am talking about!!! The el cheapo engine can be done if you follow my advice and for about $250 smackers using NEW equip. a good tuned/muffled pipe to keep the racket down will cost ya though.

Feel free to contact me degreeoff1@yahoo.com

good luck

[big_p]

Hi!!!
This is my first post. I was searching on google about a weed wacker outboard and found this! I'm glad to be here. This is right up my alley.

I made one of those before. I still have some pictures that I'd like to put on here sometime. It was very simple. I found a small 2 bladed prop from a Cruise n' carry outboard at my local marine consignment shop (Wickford Marine Consignment, North Kingstown, RI) and a standard Weed Eater brand engine. It had a curved shaft. All I had to do was just bend the shaft a little more. It was not a big deal at all. I stuck it in my vice and bent it a few inches at a time in different places (so I wouldnt kink the cable inside). Mounting the propeller was the only hard part. I had to bore it out a little using a dremel. In the end I drilled a hole through the propeller and weed eater shaft, and stuck a cotter pin through it. for the mounting of the weed eater to the boat: I got the clamp assembly off an old 3.5 horsepower Eska that I bought on ebay. I had to put an adapter around the weed eater shaft, because it was much too small. I mounted a throttle cable that led to the tiller. I put it on my friend's 14' boat (that had a 25 on it) and I hit 2.5mph :D

I am currently working on a 1.2hp Eska that I am putting on a 2hp Tecumseh engine on.

[Jack Jackson]

Im currently trying to design a way to drive my 12' pirogue with a weed eater engine i recently picked up for free. I know it probably sounds dumb, but I believe it can work. However, I don't know how to find out what size/type/pitch prop I will need. I am hoping to have direct drive for simplicity. I don't know the exact specs on the engine yet, but most weed eaters are around 30cc. I would estimate its power at 1HP at best. Any information is greatly appreciated, and let me know if you need more information on the engine/boat.

I have seen this done with a Flexable shaft weed eater. I also know how to do it with a straight shaft hh=ook up. Both require a bearing mount next to the prop. If you are still interested, please e-mail me and tell me what type you have.
Jack Jackson
Houston, Tx

[Kurt]

I am planning on turning a jon boat into a bass boat and i would like to have a center console with stearing. Is there any way you can get a hand controled 5 hp outboard motor and make it so that it can be controled through a stearing wheel? Is there a way to wire it so it can be controled through a stearing wheel? If any body can help please reply.

[gonzo]

You can use a cable and pulley system. If it doesn't have a hook-up for shift and throttle you will have to fabricate them.

[Frtaz]

Like Ward Said,
Im currently trying to design a way to drive my pirogue also with a weed eater engine! However, I don't know how To hook up the prop, what type of prop do I need to use. I am Useing a Weed Eater 32cc brand weed eater straight shaft. Any information is greatly appreciated, Does anyone have any pix that I can see how they did it also.

[gulfcoast crabb]

Ok i tried it already, the weedeater egine is not going to have enough power to push the water its going to bog down when you put the shaft in the water. you need something a little bigger about a five hp with a horizontal shaft. I'm from louisiana and we do this kind of thing all the time. If youre doing on a pirouge, the boats not big enough to control from the back of the boat, so a go devil or aircooled outboard is out of the question f it is a true pirouge, the best thing to do is get a small shaft machined and mont the motor inside the boat where the boat will still be balance right. the shaft should come out the back right on the bottom and sides meet in the back if this makes sense then you need to make a bracket to hold a rudder over the back of the boat almost like what you would find on a sea kayak then you just fab a control for the rudder so you can control it while sitting in the middle of the pirouge. If you do it like this with a very small prop you might be able to get away with the weed eater engine, but all of the ones that i have seen have at least a 5 hp. when i did it i was going to try to make a motor simular to a go devil but the weed eater wouldnt run when i put the prop in the water (i tested it in my swiming pool) also it would be very hard to control an motor like that is something as unstable as a pirouge. If you did want any other help with this i could answer any questions you run into. these are exactly the kind of projects i'm always working on
Phillip, phillipeit@cox.net

[DUCKSHOT]

Howdy Ward
Just wondered how the motor came along a 2 years later. I just bought a 13' flat back pirogue and was looking for an air cooled motor to get the job done as well. If you have any recomendations let me know. Thanks
Ben

[ddomp]

please visit my web site at www.weedwhackerboat.com. please feel free to contact me with any questions. I also hold the U.S. patent on this product.

[ddomp]

please visit my web site at www.weedwhackerboat.com. I hold the U.S. patent on this product. please feel free to contact me with any questions.

[ddomp]

please visit my web site www.weedwhackerboat.com. I hold the U.S. patent on this product. Any questions please feel free to e-mail me. sdomp99@yahoo.com

[ddomp]

please visit my web site www.weedwhackerboat.com. I hold the U.S. patent on this product. Any questions please feel free to contact me at sdomp99@yahoo.com

[Yuengling]

this technology ate my typing so now you get short version. lucky you! just put a small paint stirrer on the end of a weedeater and it will work pretty decently. I figured this out using a barrel with water. if you use a big bucket of water you'll figure out more. have fun and get wet. oh yeah when you are in the boat going thru the water and thinking cool this works, don't forget to turn or stop somehow. robert.

[weedeater]

[=im trying to make a weedeater boat motor but when i put my prop in the water my engine stalls what can i do any info on any weedeater conversions would be greatly appreciated

[weedeater]

I Put A Big Propeller On My Weedeater And Just The Wind It Generates Pushes My 12 Foot Boat Perty Good Does Anyone Got Any More Ideas Or Modifacations For Weedeater Conversions Im Very Eager For Some Feedback

[weedeater]

[there Is A Lot Of People Using Weedeaters As Boat Motors For Them Not To Work Dont You Think

[weedeater]

this technology ate my typing so now you get short version. lucky you! just put a small paint stirrer on the end of a weedeater and it will work pretty decently. I figured this out using a barrel with water. if you use a big bucket of water you'll figure out more. have fun and get wet. oh yeah when you are in the boat going thru the water and thinking cool this works, don't forget to turn or stop somehow. robert.



tell me more

[millrtim247]

Weed's comment about the enough wind alone to move his 12' jon boat reminded me of a question I asked about a year ago. would a small engin put on a 3" dia fan move a 12' canoe with 250lbs in it?

[millrtim247]

here's a quick sketch. I dont have the fancy cad /web designer programs. Just a pencil, an imagination and the willingness to try anything that'd be cool, fun or original.

[millrtim247]

Since this has gotten NO reply at all as it did a year ago, I'm assuming it wouldn't work.If however I do get bored and cant come up with a fun project by summer. I will give it a shot anyway and let you all know how it turned out.

[trialnerror]

it happens this week end home made out board blackndecker two stroke weed eater no clutch no flexi drive starts whith prop in waterplenty of push in test tank going on the back of a 14 foot tinny going to thrash the hell out of it see how long it lasts

[john_van_v]

I am thinking that maybe a nozzle arrangement around a sharp edge propellor would accomdate the high RPMs..

Just an idea

[FordManiac1112]

Hey all i just started an idea i had for the weed eater prop plan.My friend Travis said he made one with a stright shaft, and I was wondering if that was possible? And if possible if i brace a 6 inch fan blade would it make my 2 person raft go?

FordManiac1112

[caveman]

I've built one of these sort of like a go devil. the trolling motor prop is the wrong direction. I will be posting some pics if you need demintions I can give them to you. The complete build cost about $175.00 if you have to buy a weedeater the best one to use is the homelite one wheel edger.But if you already have one maybe you can adapt it or get back with me and I might be able to help you with it. The one I built works greats it catches a lot of abuse in the swamp. It sure beets paddling. The motor is big enough to turn a 8" prop but you have to block the cutch to direct drive. The prop can be made from a peice of sheet metal. depending on the type of running your going to use it for depends on the size an pitch I a 6.75 x 4. But if your just in open water a 8 x 4 will do fine. please contact me I have more the enough info to help you out.

[yotphix]

If the trolling motor prop is the wrong direction, just put it on the other end of the boat! Like a trolling motor!

Does a weed eater motor work tilted at an angle? If so has anyone tried to do a Thai longtail with one?

[caveman]

Hey Ward, remeber this pharse "less is more" do litsen to these guys I have a working drive that i will be glad to share with you. Some of these ideas are very good but to much thinking involved. The mount is simple and the prop can be made with a piece of sheet metal using a vise and a hammer. And to all you folks out there think a flex shaft won't work because of under water or to much torq tell that to the one I use every year for hunting three month out the year in 2" of water with 14' round bottom pirogue running mud hitting stumps for the last 5 years and still running stong. just cause you may live here doesn't mean you have seen every thing. I've been there done that and still doing it and so is half the people i hunt with that have one I made for them. Ward I will help you with this matter and by the weekend post some pics for all you engineers out their. Ward if you want I can make the pieces for you and send them. I work for a plant in maint. and have alot of time on my hands.

[caveman]

Yes they work tilted don't you use one on your grass. Most engines can be turned on the shaft anyway.

[caveman]

Here is some pics of my motor that been working fine for 5 years. So feast your eyes we might be "COONASSES" but we know our boats & motors.

[ripped off]

Wow ddomp, aside from the improvised rod holder for a mount, thats pretty much a carbon copy of my first prototype that I posted pics and info about on various forums two years prior to your patent date.

To all the nay sayers out there, I can tell you that this does work, and works well if done properly. Having done a lot of experimenting and having refined my design many times, I found that the electric trolling motor props are not the way to go. They will work to an extent, but as mentioned by someone else, they bog way down under load. You need a small prop with a shallow pitch. I found a 5 1/2" 2 bladed prop to be ideal, and even had good success with a 3" 3 blade prop. Of course I took my design alot farther than merely slapping a Walmart prop on a weedwacker. I ended up taking mine from a "conversion" to a scratch built drive made from thick walled aircraft aluminum tube with a TIG welded skeg, full bearings and seals. I found a straight drive (styled after the long tail mud motors) to work best. I push a 14' wooden duck boat with mine and it will do about 5 mph fully loaded with lots of gear. It also does very well in weeds. Heres some pics of my refined design.

http://i82.photobucket.com/albums/j244/Turn4fun/motorside.jpg
http://i82.photobucket.com/albums/j244/Turn4fun/motorrear.jpg

[jndbyrne]

Good job. Best design I have seen. I'm trying to do something similiar for a 1 man pontoon boat. Where did you find the propeller?

[Greg Berlocher]

AttN: Ripped Off

Nice looking power plant. I am the Kayaking Editor for Texas Fish & Game magazine and wanted to see if anyone has mounted your engine to a kayak. If your schedule allows, please drop me a note at kayaking@fishgame.com.

Best Greg

[burns142]

Attn. Ripped Off,
Where did you find a prop like that or did you make it, would like some info about that if you don't mind. burns142@yahoo.com

[ripped off]

I've built a few of these units in the past 5 years for friends. I don't know of anyone using one on a kayak as we use them for duck boats, but I'm sure one could power a kayak quite well with it. I'm stepping my design up once again, and this weekend will be fabricating one with gear reduction.

[jndbyrne]

Attn: Ripped Off

Would you contact me at jndbyrne@flash.net. I would like more info on your reduced gear design.

[DUCKSHOT]

Ripped off could you send me an email at benrod2@yahoo.com?
I'd like to ask some questions about your motor which looks awesome!

[Greg Berlocher]

I have some questions about the prop and tiller mount. Could you please e-mail be at bigredfish@aol.com. I sure would appreciate the help. Thanks. Greg

[Jimbo1490]

I want to make one of these myself. For the benfit of all looking at doing this, you should check into using an RC boat prop. Most are for super go-fast boats, but not all. There are RC tugs and the like as well. Here's a few item #'s I dug up on ebay that might work OK:

6015534980
150002787430
150028259797

You could email that seller and tell him what you are up to and he could probably make a recommendation. Weedwhacker type engine conversions are common in the RC boat world, FYI.

The pricing is very reasonable given the precision of these props. Octura makes a bewildering variety of props, so they probably make one that should work well.

Jimbo

[DUCKSHOT]

Hello where is evryone at? Did someone get a reply from ripped off or caveman and not sharein?
I've noticed that these 2 cats have looged on but not replyin.
Anyone get some good ideas?
The split here in Louisiana is gunna start in about 2 weeks and I'd like to start my motor before the split stops and starts again.

[DaveH1]

Great thread, let's keep it rolling.

I am converting a sit-on-top kayak to a lay-on-my-back duck hunting scull boat, had thought about cutting the shaft on my trolling motor.

This would essentially create an ultra-short-shaft (like 7-10") electric outboard mounted on a fabricated transom.

Now y'all have got me thinking about going with a mud-motor orientation similar to Ripped Off's rig. Fewer design challenges with steering, plus the rig could be more easily moved to one of my canoes if I wanted to.

Ripped Off, is your transom mount pivotable side-to-side, or just up and down? It looks fantastic!

thanks,

dave

[sledhead]

i was just talking to a friend of mine about doing this. alot of lakes up here do nott allow gas engines because of the oil into the water factor. this will work great cause they can't say a whole lot when no oil is floating behing the boat. we are getting too old to paddeling the boat back after the battery has died from trolling.

[wblakewsx]

forget the 90 degree turn, do it like they do in Thailand

[DaveH1]

Is it time to think about adding a removable Kort nozzle to this rig to improve efficiency when traversing deeper water?

A nozzle would probably impede progress in muddy conditions, so making the nozzle in a manner that loosening a clamp would allow it to be slid up the shaft, then reclamped once it is above waterline might be best.

If it were detachable from the shaft, it would be one more thing to get lost/misplaced...

thoughts?

dave

[sledhead]

got the thing all set up. had a lot of trouble finding a prop to fit the shaft ont the weedeat, then the shaft turns the wrong direction. so i flipped the prop and it works. granted won't be as effective due to the prop working ing reverse.

now i'm making my own version of a Go-Devil. have a 5hp briggs i'm rebuilding with a little extra umph. gonna run a shaft out about 5 foot and mount the prop. should work just as good as the go devil but cheaper.

[gonzo]

Flipping a propeller around doesn't change the way it turns.

[zero gravity]

has anyone done a twin weedeater setup?

reason I ask is I got a 15' gheenoe 110 lbs fiberglass hull and I'm looking to push it between 10 to 15 mph

I got two weedeaters not sure on the cc's ,got all the way through this thread saw that "ripped off" got his up to 5mph

so I guess my question would be would twin weedeaters get me up to at least 10 mph? thanks in advance for any help or advice

ohh this is my first post by the way
great thread and site
have you guys seen the weedeater outboards on smalloutbardmotors.com

[gonzo]

You need four times the power for twice the speed. However, because you are also adding weight and drag with a second motor, it is probable closer to five times.

[sledhead]

making both engines run the same speed may be a problem also.

[zero gravity]

thanks for the input guys

I was thinking of connecting both trigger accelerator cables to a single trigger

the setup would have both engines mounted on a single horizontal bracket with a pivot point x axis single shaft on both fabricated from aluminum tubing with some sort of skeg on both. Guess I would need to place a stabalizer bar or tube between the two output shafts to keep them from flexing when turning. Fab up a tiller handle with trigger and engine stop button wired to both engines and make some exhust tubbing so it runs down towards the props

I'm a rookie when it involes twin anything but would one weedeater have to right rotation and the other left or would I get away with both being right?

went out to look at the weed eaters I got there both 31cc guess that might not work for the speed I want 10 to 14 mph mayby two 55cc's might get it there. The boat a "gheenoe"wieghs 110lb I come in at 250lbs. Hull has had a 4hp 2 stoke on it that pushed it 12mph on a plane on a good day with the wind at my back and it has had a 15hp which was like riding a jet ski topped out at 24mph
so my main concern would be to get it up on a plane at a low speed mayby a mod to the output shaft with a hydrofoil copy made out of sheet metal might help with getting up on a plane for this low hp setup

gonna make up some drawing tonight not on cad or anything like that just a simple sketch

agin thanks for all the input

[donochud]

if you just take the spool off the end of the weed eater and replace it with a prop from a trolling motor. you can mount the weed eater on a 360' swivel caster just below the throttle handle. it will push two grown men in a canoe at
5 mph

[PAINTBALLER1244]

Hey Guys I Have Successfully Made One Of These,if Anyone Wants Pics I Can Sent Them To You Ro Tell You How I Did It.

[sonycrayfish]

Send it to me!

Sonycrayfish@yahoo.com.com

[PAINTBALLER1244]

sure here they are,its a boldens 31cc

[ripped off]

Looks good. I used a similar homemade prop at one time and it worked OK, but not as well as the ones I use now. If you want to try one out I'll PM you with a link to my source.

[PAINTBALLER1244]

yes,please that would be gr8,im always open for ideas to improve design

[DaveH1]

Welcome back Ripped Off!!

Glad to see you hadn't disappeared from the Internet.

How'd duck season go for you?

Can you PM me your prop source?

What size of drive shaft do you use inside the aluminum tube? What seals and bearings do you use to support it?

Thanks,

dave

[PAINTBALLER1244]

Actually There Is 4 Sealed Bearings In The Bottom But I Still Packed Marine Grease In It Intil It Came Out The Sides,theres 2 Pinion Shafts In The Bottom And Ther Is 2 Bearings On Each There About 1 Inch In Diameter,i Am Still Interested In The Prop Link You
Have.

[PAINTBALLER1244]

Oh Yeah The Shaft I Believe I Made From A 3/16 Rod,steel

[kengrome]

Looks good. I used a similar homemade prop at one time and it worked OK, but not as well as the ones I use now. If you want to try one out I'll PM you with a link to my source.

I would like to try your source if you're willing to post it or email it to me, thanks!

[PAINTBALLER1244]

acually i did it all myself and made all my own part to make it work,i could tell you everything i used if it helps?

[ripped off]

OK, I intentionally neglected posting or replying to emails on this for the last few months because I'm a firm beliver in letting people figure things out for themselves. I figured that posting teaser pics of a successful modle with no directions would spark folks to tap into their creativity and start experimenting rather than assembeling pieces from a parts list. Appearantly there are more people on here that prefer the latter rather than the former. KUDOS to those of you who did take the leap and come up with working designs of your own. Heres how mine are built.

Materials list:

* 5' length of 1.00" x 0.125" wall aluminum tube (drive tube)
* 5' length of 3/8" stainless steel round rod (drive shaft)
* 4' length of 7/8" x 1/16" wall aluminum tube (handle)
* 15" x 4" of 0.10" aluminum flat (for skeg, will make 2)
* 2" x 4" x 1" thick aluminum flat bar (universal mount)
* 3 bronze plain bearings, 3/8" I.D. x 1/2" O.D.
* 3 bronze plain bearings 1/2" I.D. x 3/4" O.D.
* 1- 3/8" shaft collar
* 3 oil seals, National/ Federal-Mogul brand #330385 (got them at O'reilly)
* 3 Stainless 10-32 x 1/4" cap screws and nuts (bearing set screws)
* T-10 prop from www.Youngprops.com
* 30 cc or larger weedwacker powerhead
* Handelbar mounting bracket for a Stihl brush trimmer





First lets start with the powerhead. Choose one that is at least 30 cc, and one that will mount to the shaft independent of the throttle grip. I also recomend that you bypass the clutch if present. Belive me, I melted the plastic housing on the trial run with my first prototype when the clutch slipped under load.

This is what I use http://i82.photobucket.com/albums/j244/Turn4fun/000_0270.jpg

About the bronze bushings; the smaller ones nestle inside the larger ones. When you go to the hardware store to get them you will notice that some will fit insde each other very easily and others won't. Sort through them and select ones that won't quite nestle. You will press them together with a vise or C clamp. Next use a 3/8" nut and bolt as an arbor and chuck each bushing in a drill or a lathe. With the drill running, work the outside down with emery cloth or a fine file until they will slip easily into the drive tube.

Cut the drive tube to be 1 1/4" shorter than the driveshaft.

Drill and tap a 10-32 hole for a set screw at each bearing location, one in the center and one near each end.

Cut the skeg plate corner to corner and file it to your desired shape, and have it welded to the drive tube.

Insert the bearings and secure them with the set screws. On the prop side, insert the bearing 1/2" below flush. On the engine side, 2" below flush.

Grind 1 1/2" of the driveshaft square to fit the engine's output shaft. Do this as precisely as possible. Any machine shop could do this pretty reasonable.

Secure the shaft collar about 3/8" below the squared off end. You may need to file the outside of the collar down a bit so it does not rub on the inside of the drive tube. The collar sits on top of the upper bearing and you'll want to adjust it so the square end of the driveshaft is flush with the end of the tube.

Press two of the oil seals into the prop end of the drive tube. Fill it with some gear oil or marine grease and insert the shaft, then install the upper oil seal.

Fabricate the tiller handle from the 7/8" tube (bend or cut and weld to desired configuration). Mount the tiller to the drive with the handelbar mounting block. Heres a pic of the mount.

http://i82.photobucket.com/albums/j244/Turn4fun/000_0269.jpg

Add the throttle grip to the end of the tiller and rig up a longer cable.

Here are some pics of my universal mount. I built this entierly with a hacksaw, files and a drill press, but a maching shop could probably whip one out for you for next to nothing.

http://i82.photobucket.com/albums/j244/Turn4fun/000_0267.jpg
http://i82.photobucket.com/albums/j244/Turn4fun/000_0266.jpg
http://i82.photobucket.com/albums/j244/Turn4fun/000_0268.jpg

This mount piviots forward unrestricted but is limited on how far back it will tip (this is to set the drive angle) and will rotate 360 degrees. The pin on the bottom is merely a 1/2" bolt with the head cut off, and is threaded into the bottom of the mount. On the boat you will need to mount the female half of a standard oar lock. In the side view you can see a slight angle on the bottom right hand side of the upper half of the universal mount. The more angle you file here, the farther back the drive will tilt. I recomend that you start with no angle at all and file a little at at time until you get the drive angled the way you want. I recomend as shallow a drive angle as possible without the prop cavitating.

Install the prop and the powerhead and you're good to go.

You will need to note that because weedwackers run at such high RPM, you will get the best performance at about 1/3 throttle. Any more than that and the thrust drops off and motor starts to bog.

Heres some more pics

http://i82.photobucket.com/albums/j244/Turn4fun/motorside.jpg
http://i82.photobucket.com/albums/j244/Turn4fun/motorrear.jpg

Note also, if you are building a "lower unit" style like Paintballer's, the prop will turn the opposite direction as the engine. I recomend the T-8 or the T-13. If you are building a straight shaft where the prop turns the same direction as the engine, I recomend the T-10.

[TerryKing]

Have you guys seen this "weedeater" design from Thailand??

[mrmoto58]

Hi your weed eater idea looks great .my son needs a small motor .thanks Ted . p.s. if you had more lower units to fit weed eater motors you could sell them on ebay .

[spyderpaintball]

ripped off, thank you for the detailed post. I have a question about the bearing set screws. how would those work? do you just put the screw straight through the drive housing to keep the bearing from sliding down? wouldnt it hit the drive shaft? would greatly aprechiate an explanation for these set screws and maybe some pictures. thanks

[TerryKing]

Here's a PDF of RippedOff's post:
http://www.terryking.us/boating/RippedOffWeedwhacker.pdf

I wanted to be able to see the photos and stuff together in the shop....

RippedOff, if you don't want this up there, let me know and I'll shoot it with my 10 Gauge Parker :-)

[z1ox]

...I'm stepping my design up once again, and this weekend will be fabricating one with gear reduction.

How did your trial go on the gear reduction? Because of other threads on this topic concerning 'bogging down of the engine' I had felt a planetary gear reducer would be perfect. The specifications for an Echo 22.8cc weedeater model SRM230 engine has ~3000 RPM at Idle and ~12000 RPM wide open. Of course I wouldnt think of using anything less than 31cc for this, but the RPMs are probably going to be near this. (I am not taking this thing to the moon, anyway!) There are some planetary gear reducers out there that look like they may be compatable but I have not been able to find any on the web that could handle 12000 RPM input. I will keep looking.

I am thinking a 3:1 gear reduction would generate more torque to allow a larger prop... I will study this some more and see what I find. The ones I have seen so far are $50-$150.

Thanks for sharing all your secrets. It was your project pictures that got me hooked, the parts list was a great bonus.

[Jimideaman]

hi
Has anyone built a mud motor using a 4-stroke gas trimmer ? Menards has a 26 cc trimmer on sale and they claim in their Ad. " provides more torque and power than two-cycle engine. It runs quieter ... ". I don't what brand it is can't tell from Ad.) The picture/text shows it to be a split-shaft / curved-shaft design. Tnx for any comments anyone has.

[paulieh]

Hey guys I'm just new to this website and are not sure how to add new post. My question is I've got a small featherlite weed eater motor and wanting to make it into a fishing Kontiki. The motor had a curved shaft so I have streighten it out. But I would like to shorten it up slightly. The shaft has a spring that has a steel square pin that goes into the motor and into the porp end. My question is how do I short it ???? Cheers Paulie.

[ripped off]

I don't want to discourage you, but before you start building get rid of that Featherlite and get something thats at least 30 cc. The Featherlites don't have enough torque to turn even a tiny prop in the water. I know a guy who built built one off of my design and used a 17cc Featherlite. It would not run in the water period. You could start it up out of the water, but the second the prop touched the water it would kill the motor. Even if you revved it up first it would still kill it. I later came accross a 21cc Featherlite for free and tried it with the same results. The smallest motor that I've been able to build a successful troller from was 28cc and it had just barely enough torque to run in the water. I've had great success using 31cc motors.

[Jimideaman]

I purchased (on sale) a Sears Craftsman Weedwacker No. 79616, 40cc 4-stroke. I'm thinking I'll fabricate an extension to mate where the split shaft accepts attachments. If anyone has had experience with this particular model and had problems let me know and I can return it. If not, all I need is the time -- if anyone has any extra unused spare time hours, forward them. Jim

[flapdoodle]

I made a translation of a Russian site featuring a weedeater conversion here:
http://www.flapdoodledinghy.com/GD.html

The original site is here:
http://iv70.narod.ru/IV/9/GD.html



I would be interested in any info you guys might be willing to share on the weed eater/ out board idea.
thanks,
Bill

[flapdoodle]

I now have my own design on the water...
http://www.flapdoodledinghy.com/motor.html

Bill

[John O`Neal]

Ripped-off ; I have read your posts on this as well as other forums aka (turn4fun) and they have been both informative and enlightening . You have shortened the trial & error curve considerably. In a recent post a writer asked if the conversion displayed on the layout boat at the Cabelas waterfowl classic was one of yours ? It was my first attempt from two yrs. ago and it suffered from all the common problems, to small of an engine 25cc, and to large of a prop (Minn-kota plastic). It made a good fan for blowing the dust off the garage floor but hated water. I put it back on the shelf as duck season had arrived. I had essentially given up on it as an unfeasible idea. Then late one afternoon at the Four-Rivers wildlife area I followed a layout boat out of the marsh, he was using what I believe to be a unit of your design. The guy was tight lipped, wouldn`t give up an ounce of information, but I had seen what I needed to. The idea was workable I just needed the right parts. Bigger engine-smaller prop. At this point I decided to build my own version of your designed long shafted weedeater conversion. I took apart my cruise`carry outboard to get ideas. It is essentially a weedeater size engine in an outboard configuration. It uses an aluminum tube with a stainless steel 3/8" drive shaft running through nylon carrier bearings, this motor is over 20yrs. old and still works great so the design I figured is a sound one. For those of you out wanting to build one of these conversions here is how I built mine. I also arrived at 5ft. as the length of the carrier tube. This was determined based on the height of the transom (layout boat) and a desired shallow entry angle of the prop into the water. I used a 1 " tube with a .065 wall thickness. This allowed me utilize a 3/8" ID x 7/8 OD sealed ball bearing ($6) on the prop end . This combination creates a 5 thou. interference press fit. Works nicely for locating and holding the bearing. The carrier bearings (2) are made from 1" nylon rod. It`s cheap, durable and readily available from plastic supply houses. I got mine from Airparts in K.C.Ks.$4 a foot. I chucked the rod up in a lathe and center drilled it 3/8" . I then turned down the OD of the rod .0871 creating a 1 thou. interference press fit. I cut off 2 pieces each 1" long they will serve as the top bearing and the middle carrier bearing. I installed them using a long wooden dowel as an installation tool. The drive shaft just like Ripped-offs is 3/8 stainless rod. I had my buddy who has an end mill square off one end to fit into the engines output receiver. Any machine shop can preform this operation. I did my first one using 4 1/2" grinder with an abrasive flapper disc. I used a 3/8" set collar above the top bearing to prevent the shaft from sliding out of the carrier tube. On the prop end I also used a youngs 5 1/2" propeller . It mounts easily with a roll pen thru the 3/8" drive shaft. I use a small spacer washer between the prop and the roller bearing. This allows the prop when under load to press against the inner ball bearing race thus transferring the thrust up the carrier tube to the transom mount, as opposed to up the drive shaft to the engines crank shaft. All you need now is a powerhead. Pay heed to Ripped-offs advice and go with the larger cc motors it will save you some frustration. Ripped-offs versions were the first in the water and I certainly don`t intend to imply that I have built a better mousetrap. I`m just offering up a different way to get there. Ripped-off; I am anxiously awaiting news on your gear-reduction model. You might want to look at Rickshaw-motors.com he has a really slick unit. FYI Youngs makes props for clockwise as well as counter-clockwise rotation

[ripped off]

Great job John. That may very well have been me at 4-riv, I get approached at the ramp at unit 4 almost every time I'm out. I've thought about using delrin for my bearings several times but never have gotten around to it. In all the years mine has been in use, I have never had to replace one of my bronze bearings yet. I used to be very tight lipped about how they were made because I always thought I would have a go at marketing them, but just never had the money it takes to get something like that off the ground. Once the 5 & 6.5 mudbuddys came out they pretty much killed any potential market for the weedwackers anyway. I found the rickshaw site just a week ago, it's amazing how much it resembles one of mine. Interestingly enough, I always talked with my buddies about using that same Honda engine and a gear reduction unit. He's got a sweet looking design, but he also has way too much reduction and it shows. It says that his units are 3.75:1 all the testing I've done suggests that 2:1 is perfect. Post up a pic of your motor and I'll keep my eye out for ya in the marsh this season.

[John O`Neal]

Paintballer1244; If "ingenuity paves the path to achievement" you are certainly traveling the right road. Great design. I think we may have used the same brand C-clamp on the transom mount. I have since gotten a little lazy and started using old trolling motor mounts that I find at flea markets and garage sales. They look good and work great.------I have a question regarding your Bolens engine. I am currently putting together a long shaft weed-eater conversion for a friends layout boat and economy is a factor. I have seen the 31cc Bolens at Lowes for $69. Certainly reasonable enough for a new unit of that size. Since the pictures of your unit were posted last March I`m sure you have had an opportunity to use it . How did the Bolens work out ? Does it have adequate power ? Does it start and run well ? Does it have any negatives? Any information regarding this engine will be greatly appreciated.

[John O`Neal]

Ripped off : Hope to have a camera soon capable of downloading to my computer. I`m looking forward to posting up some pics. As for seeing you in the marsh, I will keep an eye out for you I`m sure our paths will cross. Like yourself, I try to hunt as many days as possible. Regarding gear reduction units. I have started building one myself. I am already in my 2nd design and am currently waiting on bearings I ordered on the net. It will be belt driven HTD 480mm20mm8mm. I found some 2 to1 ratio pulleys (as per your testing)for next to nothing used. The pulleys come from the racing industry and are used on stock cars ,dirt modifieds, etc. They are abundant on the used market. I had hoped to have it ready to test within the month, but duck season is rapidly approaching, and as my wife says " you never get a d** thing done around here when those ducks start flying" If you see a white trailer, double layout stacker with a DU license plate in the parking lot at 4riv, keep an eye out I`m in the marsh.

[John O`Neal]

Ripped off : Hope to have a camera soon capable of downloading to my computer. I`m looking forward to posting up some pics. As for seeing you in the marsh, I will keep an eye out for you I`m sure our paths will cross. Like yourself, I try to hunt as many days as possible. Regarding gear reduction units. I have started building one myself. I am already in my 2nd design and am currently waiting on bearings I ordered on the net. It will be belt driven HTD 480mm20mm8mm. I found some 2 to1 ratio pulleys (as per your testing)for next to nothing used. The pulleys come from the racing industry and are used on stock cars ,dirt modifieds, etc. They are abundant on the used market. I had hoped to have it ready to test within the month, but duck season is rapidly approaching, and as my wife says " you never get a d** thing done around here when those ducks start flying" If you see a white trailer, double layout stacker with a DU license plate in the parking lot at 4riv, keep an eye out I`m in the marsh.
" ingenuity paves the path to achievement"

[rangersboat]

I am working on something like this too, I have a roybi 31cc weed eater and I hope to put a prop on it to run my 12 ft boat. One question about go devils, does a 2 hp 4 cycle engine need a oil pump to be a go devil? Go devils run at angles so they might no get oil. any help would be nice.

[Syed]

I have a SACHS 309 two stroke engine, starts and runs great. I do not know its power/cc ratings. Any help about its power rating will be appreciated as I want to enter into the arena of weed eater conversion.
Thanks,
Best,

[John O`Neal]

My layout rig

[bgtreefrogs]

After years of researching I’m going to take the plunge and build one of these for my kayak. THANKS FOR ALL THE EXCELLENT POSTS! This is the best resource on the web. After reading the posts on the engine sizes I decided on a scooter motor as opposed to an actual Weedeater. The cc’s are larger and they are cheep. It looks like I can also get one with a heavy duty clutch and reduction gear (scooter transmission), also an electric start. I was curious about ripped off’s comments about removing the clutch – it seems that this may not be required if the clutch was actually designed for heavy duty use. You can also get some that have double bearings and three shoes rather than two. Also, the reduction gear might eliminate the need to remove the clutch, since the engine will not be too stressed from the start. I’m going to follow ripped off’s design, which seems bullet proof. Outstanding Design! Any comments? I understand the scooter transmission is a 5:1 reduction. I know this is more than the 2:1 and 3:1 that has been discussed here, but it is already built. Would be great if I could use it rather than use some pulleys and gears.

[crokseti]

I, m working on a project myself and am trying to adapt a Ryobi 31cc motor with a homemade3 bearing shaft conected to a edger gearbox to which a small prop is affixed.
I'll purchase a Sears gearbox with 1-to-1 ratio unless anyone here can direct me to another brand that has 2-to-1 gearing.
Sears-Poulan is around 30 bucks.
I hav'nt found any info on the ratios of any edger gearboxes.
I went to Sears and turned one by hand and verified 1-to-1.
Any help would be appreciated as this project will be done regardless but I don't have much cash to work with.
I will get the prop from Young's.
Thanks,

[evlfkrjohn]

Hey guys i'm new to the site but have been pondering the same ideas! This is the best way that I have yet!! It works flawlessly!!!!!!http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMEWA%3AVRI&viewitem=&item=150215327520&rd=1

[master fisher]

how did u make the weed eater motor please explain if u have time please email me at maddogmd2005@hotmail.com

[master fisher]

The engine is really not that loud, but anything beats paddling :P

It appears that this is the best way to mount the engine. The pull start, handle, and throttle trigger are all in great locations. the handle could be used as a tiller. I do see a couple of problems however. First, this is rotated 90 degrees counter-clockwise from the way you would hold it as a weed eater, which puts the fuel tank filler cap facing forward. Not a big deal, I could always just mount a new tank. This one is part of the handle, so I can't just remove it and rotate it. Another possible problem I see is the location of the spark plug. It looks like its just asking to get drenched, and short out. I'm thinking some sort of small shield to surround it should be sufficient, as this will never see high speeds. Other than that, the only real problems left are figuring out how to mount it to a transomless pirogue, as well as finding/making a suitable prop.

I have thought of one other thing, however. most weed eaters are designed so that the engine can be easily removed from the shaft, in order to change from say a trimmer, to an edger. An edging attachment has a gearbox at the bottom, at a right angle to the shaft, with some gear reduction. I may see if I can find one of these, and see what type of gear reduction it has. I'm thinking it might just be enough to be able to use a small trolling motor prop.





take a pipe and run it from the muffler and run it into the water it is much quieter

[SSNgineer]

Hello everyone. I've been watching this thread for a couple years and I finally have something to contribute. I've been working on a gear drive design based on a 4-1/2" angle grinder head. The gears are made for higher RPMs than a trimmer engine but may not hold up under the higher torque. I haven't done the stress calculations yet. The grinder I bought at Lowe's was $30 and has a 3.08:1 ratio. I am turning an adapter on my mini-lathe that I designed this weekend. I'll try to post some pics soon.

I'm also creating a solid model in Solidworks for a new housing for these gears. It would look better, but I'm not sure how much it would help for reducing drag or cavitation. I plan on using a Weedless Wedge 2 prop that I found on closeout at Walmart and either my 30cc Ryobi (Homelite engine) or Stihl FS46 for power. Using the formula from Minn Kota's FAQ section, I calculate about 8 MPH at 7000 engine RPM (2270 at the prop) assuming 15% slip.

Has anyone tried the grinder gearbox idea before? What do you all think???

[evlfkrjohn]

Hey guys, sorry for the slow responce but my computer has been down for a couple of weeks and i've finally got it back up! The design isn't mine, I got the plans from livetofly57 on ebay. The plans came with all the info on how and where to get all the parts needed to do the conversion. It is a very nice design and was very well thought out! My nephew is welding up an aluminum foot for me in the same design as a 40lb motor-guide trolling motor to make another conversion. I will contact the seller about posting the conversion again, I would do it myself but I assured him that I would not expose his idea to everyone. But I can say this much, it has a 4:1 gear ratio that is awesome!

[evlfkrjohn]

Hello everyone. I've been watching this thread for a couple years and I finally have something to contribute. I've been working on a gear drive design based on a 4-1/2" angle grinder head. The gears are made for higher RPMs than a trimmer engine but may not hold up under the higher torque. I haven't done the stress calculations yet. The grinder I bought at Lowe's was $30 and has a 3.08:1 ratio. I am turning an adapter on my mini-lathe that I designed this weekend. I'll try to post some pics soon.

I'm also creating a solid model in Solidworks for a new housing for these gears. It would look better, but I'm not sure how much it would help for reducing drag or cavitation. I plan on using a Weedless Wedge 2 prop that I found on closeout at Walmart and either my 30cc Ryobi (Homelite engine) or Stihl FS46 for power. Using the formula from Minn Kota's FAQ section, I calculate about 8 MPH at 7000 engine RPM (2270 at the prop) assuming 15% slip.

Has anyone tried the grinder gearbox idea before? What do you all think???

I've never thought about using a grinder gear box before, but it may work well! I guess you won't know until you try! Good luck and keep everyone posted!

[Guest625101138]

.....
Has anyone tried the grinder gearbox idea before? What do you all think???

The attached pictures shows internal of a small grinder box after 20 hours use swinging an 8" prop. It was pedal powered with speed steup up to the prop so would be better in the other direction. The prop shaft was connected to the tiny pinion. I was surprised that it held up for a reasonable period.

It was very easy to replace the armature with an 8mm aluminium shaft and use the plastic case for shaft support. The removal took about 1 hour.

Rick W.

[John O`Neal]

After years of researching I’m going to take the plunge and build one of these for my kayak. THANKS FOR ALL THE EXCELLENT POSTS! This is the best resource on the web. After reading the posts on the engine sizes I decided on a scooter motor as opposed to an actual Weedeater. The cc’s are larger and they are cheep. It looks like I can also get one with a heavy duty clutch and reduction gear (scooter transmission), also an electric start. I was curious about ripped off’s comments about removing the clutch – it seems that this may not be required if the clutch was actually designed for heavy duty use. You can also get some that have double bearings and three shoes rather than two. Also, the reduction gear might eliminate the need to remove the clutch, since the engine will not be too stressed from the start. I’m going to follow ripped off’s design, which seems bullet proof. Outstanding Design! Any comments? I understand the scooter transmission is a 5:1 reduction. I know this is more than the 2:1 and 3:1 that has been discussed here, but it is already built. Would be great if I could use it rather than use some pulleys and gears.Scooter motors are available in larger cc and hp ratings . The Chinese versions can often be purchased for around $150.00 with electric start and a 76mm clutch. I have seen transmissions offered in a 3 to 1 ratio. Try a Google search for motorized bicycle, scooter parts ,mini bikes, you will find an abundance usable parts. A simple method to the bulletproof design that Turn4fun offered up is to start with a brushcutter. They come with much larger cc motors than weedeaters and make a simple ,lightweight more powerful mini-longtail conversion. examp. www.Duropower.com offers a 51.7cc brushcutter for $179.00.

[smoothseas200]

Hello Everyone,

I have the plans for this conversion for sale on Ebay. Many thanks to
evlfkrjohn for referring me to this site. This is a proven design, take the time to read the entire ad as it is a bit lengthy but well worth your time. It has been designed as simply as possible. Please see Ebay Ads :
250217316299 and 250217516279, both are my ads and both ads represent the same plans. This little motor will get the job done ! Who ever thought a weedeater could be this much fun !

Thank you,

Dean / jeta2008@netcommander.com

[smoothseas200]

Hello,
I am new to this site and I have posted my Ebay Listing Numbers to purchase the plans for a proven, easy to build, lightweigt Weedtrimmer Outboard using a 31cc engine. Anything less is fruitless. I spent a fortune in the design of this outboard. Please see the ads, this is your answer to your problems. This is the design evlfkrjohn was refferring to. I am a Aeronautical eng, so I crunched some numbers and created this little monster. It can handle a 24' sailboat with ease and larger, and cost around $ 140.00 to build as "New".
I wish you the very best, please let me know if I can help.
Sincerely,
Dean
jeta2008@netcommander,com

[realmanofgenius]

I've been using this site as a reference and have tried making one of these darn things but have hit some snags. First of all I tried to keep the lower gearbox on my Stihl FS85 trimmer/brushcutter. The problem that I experienced with this is that the force of the water being pushed by the prop would push it deeper and deeper into the water. To correct this problem I need to either shorten the shaft to about 35" so that the prop is pointing more horizontal, or I need to take off the gearbox and have the prop directly off the back of the driveshaft. I would like to have the prop directly off of the driveshaft but am stumped on how to do so without my driveshaft sliding out the back end??? Any help would be much appreciated!!!

[crokseti]

Ive almost got one built and am waiting for the prop from Youngs.
Cant wait to try it.

[crokseti]

I made my shaft out of 1 in. pipe and inserted a bearing in either end.
Had to ream it out a little to accept it but its snug. Then I used set screws to hold the gearbox and motor on the shaft.
I sealed the gearbox as best I could with form-a-gasket and painted the whole thing with hammertough paint.
I added grease fittings in the gearbox and the shaft also.
Come on Young's.

[SSNgineer]

Okay, so I tested my first prototype, based on a Homelite Trim Lite 26cc trimmer that I got at a tool sale for $40. It has a 7/8 aluminum tube, so I had to modify it a bit to work. I JB welded a 1" dia. section onto the cut down 7/8 shaft and then welded a 90 degree 3/4" electrical conduit elbow at the end. I made a skeg and two more veins and spaced them 120 degrees apart. I will later mount a duct on these to straighten and direct the flow to the prop. I turned the trimmer output shaft down and made an aluminum tapered cone to go down to 1/2" dia. I am using an Octura 0977 prop, which has a 2.7" pitch and is just over 3" dia. The transom clamp is two small c-clamps JB welded into grooves on the trimmer handle. a piece of copper pipe is used as a bushing between the handle and the shaft. I have yet to finish the tiller, but will use the lower section of 7/8 tube cut off of the trimmer, the foam rubber handle removed from the top section, and a bicycle brake handle salvaged from an old scooter.

I ran it in a garbage can today and it made very impressive thrust. It will start right up with the prop in the water and idles nicely. I noticed some cavitation coming off the center of the prop shaft under power, so I made a nice little tapered cone to screw on after the prop. I found a .120" thick polycarbonate glass at Walmart tonight for < $2 which I will cut up and make into a duct or Kort nozzle to preload the prop. Hopefully this will eliminate any cavitation and improve the efficiency a bit.

The gear driven version based on a grinder is still in the works. The direct drive prototype was the quickest to build, so I am finishing it first. I have a little more machining to do on the new housing before attaching the main shaft tube.

Also, I bought a rusted up 1954 3HP Hiawatha outboard with a very lightweight, usable lower unit. It has a 1.7:1 reduction and a water pump if I want to do water cooling. Also, I can run the exhaust straight through the fairing. That combined with an adjustable transom clamp should prove to be a nice little combination to mount a trimmer powerhead. I will try to post pics soon.

[smoothseas200]

Hello everyone, I have a time tested proven design that can easily be built just like a brand new outboard for $ 140 - $ 160. I supply parts lists, and the vendors. The plans are easily laid out with drawings, dimensions, and written instructions. After gathering the parts you can build this outboard in 8-10 hours. This is simply the way to go, once you hit the throttle I guarantee you will smile. All "Bugs" have been eliminated, period. Alot of time and money went into the developement to get it RIGHT ! I am selling these plans for $9.95 a set and will be delivered directly to your computer in PDF format, so you can have the plans in a few minutes. Just remit a Postal Money Order for $9.95 made out to R.D. Moss and mail to :

R.D. Moss
261 Julia Circle Apt 15
Sulligent, Alabama 35586

Please be sure to include your email address with your Money Order, as I will send the plans instantly after reciept.

All inquiries please direct to : jeta2008@netcommander.com





1960819608

[mmartin]

Hey Guys,

I have thought about using a weedeater to make an inboard or staraight shaft mud motor. But why use those wimpy ones when you can get a brand new surplus 4hp Tecumseh, horizontal shaft engine for $ 120.00 from these guys: http://www.surpluscenter.com

It could be easily mounted and speed reduced like this site does:
http://www.asmomarine.com

I have not done one like this, but It should work and have plenty of power, unlike those little 33 cc jobs. It could be skeg mounted as well on a little launch. If anyone tries this let me know how it works.

Ps new memeber, first post!

[mmartin]

I just made the conversion. The 4 hp Tecumseh engine I mentioned is 5.2 cubic inches which works out to 85.2 cc. @ 3600 rpm, wt. is 15 lbs. There are also two models available for less money in a vertical shaft version, same hp (4).

[Orphanedcowboy]

One thing I need to clarify, mainly for my conscience.

I saw a very similar set-up and copied it with out thought, I am not trying to pass this off as my design, I built it then realized I had seen the original while researching this. Look for a post by Caveman on page 4 of this thread.


I just finished it this morning. I built this with the Hybrid Series of boats in mind, but it should work fine with any small 8' - 10" pontoon style bass buggy. You can use a piece of angle iron clamped to the transom with a hole for the caster swivel.

Please let me know what you think, thanks!

Weed Wacker Build Notes:

Brushcutter:

Ryobi BC30

Engine Construction: 2-Cycle
Engine Displacement (cc): 30 cc
Engine Torque (Ft. /Lb.): 0
Fuel Mix Ratio: 50:1
Fuel Tank Capacity (Gal): 1 Gal
Fuel Type: Gas & Oil Mix
Horsepower: 1 HP
Assembled Weight: Less than 15 lbs with fuel

Caster Swivel $6 @ Ace Hardware
1" Shaft Collars $7 @ Ace Hardware
1/2" ID x 1 1/8" long Steel Bushing $2 @ Ace Hardware
5/16" ID 1/2" OD x 3/4 long Plastic Bushing $.60 @ Ace Hardware
Young’s Prop T-8 Prop $18 @ eBay
Throttle Cables: $1-$8 on eBay, be sure to check the length
Throttle Handle/Lever: $11 on eBay, lever was for a Stihl FS 80
Tiller Handle: $3 1/2” metal conduit from Lowe's
Handle Bracket/Cross Block: Free/Came with the Brushcutter

The first thing you will need to do is remove the upper shaft. It is held in place with a #10 screw and a bolt thru the lower part of the housing that holds the throttle cable and kill switch in place. Be sure to keep the spring located inside the upper shaft around the drive shaft. Keep the upper shaft; you will use it as a jig to make your motor mount.

The lower shaft will need to be modified to fit the housing. The upper shaft has a slot that clocks it’s orientation in relation to the housing. This slot will need to be added to the lower shaft. The shaft will need to be clocked in order to make sure the prop will be in the correct location. Use a marker to mark the tab inside the housing.

Then push the un-modified lower shaft into the housing and mark it. Use a dremel to cut the slot, once the slot is the correct depth, drill the hole for the retainer screw. Be careful not to drill the drive shaft inside the housing. Remove the lower shaft from the housing, and place the spring around the drift shaft. Re-install the lower shaft, install the retainer screw and the lower housing bolt, then tighten both, making sure no to over-tighten the 2 screws.
To make the mount use the upper shaft that you removed for your jig. Put both split lock collars on the shaft and orientate the bolts and use a belt sander to make the opposite side flat. I used 4” spacing on the collars after they were modified and welded the 1” wide flat strap on. Weld on the 1/2” steel bushing, I used a 60/40 offset on the pivot bushing, this way if I cannot get the desired angle I can rotate the mount. The plastic bushings will need to be ground to an overall width of 1 1/8”. Let everything cool then remove the mount from your jig, prep for paint, install the plastic bushings and then install on your weed wacker motor.

I used a T-8 prop from Young's Props, http://www.youngprops.com/ mounted to the original string trimmer head bolt that came with the brush cutter. The diameter is 3/8” and is the same diameter as the hole in the prop. Slide the prop all the way down against the hexagon shoulder and then carefully drill the 1/8” diameter roll pin hole. The prop is significantly softer than the shaft, so do yourself a favor and use a sharp drill and a drill press if possible. Once you have the hole drilled and the roll pin installed, cut off the shaft 1/8” longer than the prop body. This will allow you to tell if there is a problem later on down the road, and it will also fully support the prop.

Next you will need to figure out your throttle and tiller handle. I choose to use the cross block/ handle mount hat came with the Brushcutter. I am still in the process of perfecting this for the Hybrid. I found throttle cables on eBay ranging from $1 to $8, figure out your length and your throttle control, twist, lever, etc. I went with a lever off of a Stihl FS 80 weed eater. Once you have your length, then you will need your angle for your tiller handle, I did this by mounting mine to my bench, then figuring out the desired prop angle I wanted.

Now your ready to make your throttle, determine what style you want, I tried a twist throttle off of a zipper scooter and wasn’t impressed. I then spent 2 weeks looking for throttle levers, spent about $100 on weed eater handlebar mounted throttle handles only to find out I liked the plain ole bicycle brake lever style. The lever I used is off of a Stihl Weed eater model FS80. This is the older style, not the newer style plastic molded lever. I decided on which cable length I needed and made the necessary modifications to fit my application. The Ryobi weed eater uses a “Z” style cable end, and most cables will be a barrel type end. I simply cut the end off of the cable and threaded it thru the old cable mount, determined my length, cut the cable again and crimped a #10 ring terminal on the cable. I then used a #8 bolt and two nuts mounted on either side of the carburetor throttle arm, and tightened down snug.

I plan on going back and soldering the ring terminal to the cable, replacing all the bolts with stainless bolts and putting Loctite on all them. I also will be painting this after I test it on a couple of jon boats, a 14' and a 10' against a 30 lb Minn Kota trolling motor. I also need to mount the kill switch, but I haven't found anything I like, but this is a small problem.

You should now be ready to test it out.

Here is a slide show of the build:

http://i53.photobucket.com/albums/g45/Orphanedcowboy/th_1b4b7495.jpg (http://s53.photobucket.com/albums/g45/Orphanedcowboy/?action=view&current=5125744a.pbw)

[Orphanedcowboy]

Hello everyone, I have a time tested proven design that can easily be built just like a brand new outboard for $ 140 - $ 160. I supply parts lists, and the vendors. The plans are easily laid out with drawings, dimensions, and written instructions. After gathering the parts you can build this outboard in 8-10 hours. This is simply the way to go, once you hit the throttle I guarantee you will smile. All "Bugs" have been eliminated, period. Alot of time and money went into the developement to get it RIGHT ! I am selling these plans for $9.95 a set and will be delivered directly to your computer in PDF format, so you can have the plans in a few minutes. Just remit a Postal Money Order for $9.95 made out to R.D. Moss and mail to :

R.D. Moss
261 Julia Circle Apt 15
Sulligent, Alabama 35586

Please be sure to include your email address with your Money Order, as I will send the plans instantly after reciept.

All inquiries please direct to : jeta2008@netcommander.com

1960819608

Southseas, This is a copy of Turn4fun/Ripped Off's design, he posted these pictures last year on another forum. Also Island Hoper Outboards has been building these for some time, nothing new and definately nothing worth paying for. I built one off of Turn4fun/Ripped Off's design and if anyone wants the plans I will give them away for FREE, just as Turn4fun/Ripped Off has done.

http://i82.photobucket.com/albums/j244/Turn4fun/yellowmotor.jpg

http://i82.photobucket.com/albums/j244/Turn4fun/yellowmotor2.jpg

[superstitch626]

Hello all this is my first post i have another source for props you can get Composite Props instead of aluminum ones http://www.smalloutboardengines.com/ has them in their parts section i have been told that these types of props are lighter and stronger than the aluminum ones. i have also been searchings the possibility of use of one of these for my potaboat but instead of using the stock gear box what do you guys think about using a angle grinder? i have seen a couple of other posts about this and im going to try and figure this stuff out.

[smoothseas200]

Hello Orphaned Cowboy,
I appreciate your criticism, but if you take the time to look at the gear box you will notice the photo you presented is nothing more than a standard weedeater gearbox turning a very small prop. My design is powerful because of the gear reduction, and is equipped with a larger 3 blade Motorguide machete aluminum prop. It is by far superior to the design you have shown, I know because I built this type during the developement of my final design several years ago and found it to be very low on power. Since you have made such an issue over paying $ 9.95 for my plans, I will offer the plans FREE to anyone that wants them just to PROOVE it is far more superior to the other designs. It is FASTER and more Powerful than any design you may have tried. You build it then come back to post your results for everyone to see.
Order the Plans at : jeta2008@netcommander.com

The Plans are FREE, Get them while you can. Alot of time, money and engineering went into this design. It was developed to achieve the maximum performance from the engine. The power is balanced from the engine to the gearbox, and finally to the large prop for a perfect blend of POWER. I am a Engineer so I know what I'm doing. I worked all off the numbers, rpm, gearbox speed and thrust test in a test tank. It puts out 8.8hp at the PROP !
ORDER THE PLANS ! THEY ARE FREE ! I KNOW MY TIME, MONEY AND EFFORT MEANS NOTHING TO YOU ! SO ORDER THE REAL DEAL NOW ! IT'S FREE ! NO MORE COMPLAINTS OK ? I have sold over 1000 of these on Ebay with NO COMPLAINTS - SMOOTHSEAS200

[Orphanedcowboy]

Mr. Moss, I don't have a problem with you making a buck. I can also respect your time and effort. But everyone who has ever contributed to this thread that has built or modified a weed eater has done so with considerable time and effort and expense. I have spent upwards of $1000 on everyday items that can be easily modified and used with out having to buy or build a gear box. I have tested the gear box on these motors for water intrusion, and it just isn't happening, so far. I have tested the motor shown on a 250+ lb 12' jon boat(the boat I plan on using it on weighs less than 80 lbs) and top speed was 3.5 mph, not flying but fast enough for me going up a river filled with stumps and trees in the dark. I have a few dollars over $200 in my first design not counting build and test time. Your design is far superior to mine, but I could care less, I built mine with little to no help from anyone else. I did take several designs and incorporate them into my final build, but we all did. This is nothing new and certainly we can all learn from each other. The beauty of these motors is simplicity. I am a duck hunter, not an engineer, but I work with several hundred engineers everyday and I can respect your time and effort you put into your education and your outboard. I just don't understand why you came into the thread and tried to peddle the plans instead of engaging people first. That is what I had a problem with.

[Orphanedcowboy]

If you use my plans you need to cut 7/16" off of the outer shaft to make sure you have enough drive shaft engagement in the clutch drive

I found out the hard way and sheared the drive shaft off, luckily I had a replacement................:( :( :( :(

[Orphanedcowboy]

Smoothseas200

Why haven't you replied to anyone who has asked for plans? I know of several that have asked, myself included and have heard nothing.

Better yet how many people do you think would buy them from this site? Your giving them away for free, I'll give you $50 to post them in this thread, problem solved.

[superstitch626]

Orphanedcowboy take a chill pill bro he sent me the designs when i asked for them. and no i am not a clone of him or something like that.

[kengrome]

Orphanedcowboy take a chill pill bro he sent me the designs when i asked for them.He totally ignored both me and my friend, so it seems he is not willing to do what he promises.

:mad::mad::mad::mad::mad::mad::mad::mad::mad:

[superstitch626]

well it took him couple of days and a couple of emails but i got it. don't know what to tell ya

[kengrome]

well it took him couple of days and a couple of emails but i got it. don't know what to tell yaYou don't have to tell me anything ...

His refusal to send the plans as promised the FIRST TIME he gets an email request tells me he is trying to avoid living up to his promise -- and that's all I need to know about him.

If he REALLY wanted to provide his plans for free he should attach them to a post in this thread so people can download them immediately. Then remove the attached file after a week or so when he is no longer willing to give them away for free. But instead he seems to prefer to play childish games by making people send multiple requests before he will bother to live up to his commitment.

[Orphanedcowboy]

This is why I have a problem with him:

Posted 06-23-2004, 01:22 AM

I am the designer of a lightweight conventional outboard motor, weighs 11and1/2 - 12lbs. It was tested at Mississippi State University as developing 8.8 horsepower at the prop. It is excellent for shallow water use in that you can change the prop depth without changing the incidence of prop, therefore maintaining centerline thrust. It can be built " as new " for under $ 200.00 USD, parts to undertake this project can be purchased virtually anywhere. There is no maintenance to perform. I currently sell the plans for $ 29.95 USD Plus $ 3.95 shipping and handling. I can be contacted at FlyBy750kts@aol.com. I forgot to mention it can be built in as little as two days - Thanks, Roy

Posted 02-23-2008, 11:46 PM

Hello Everyone,

I have the plans for this conversion for sale on Ebay. Many thanks to
evlfkrjohn for referring me to this site. This is a proven design, take the time to read the entire ad as it is a bit lengthy but well worth your time. It has been designed as simply as possible. Please see Ebay Ads :
250217316299 and 250217516279, both are my ads and both ads represent the same plans. This little motor will get the job done ! Who ever thought a weedeater could be this much fun !

Thank you,

Dean / jeta2008@netcommander.com

Posted 02-26-2008, 03:04 PM

Hello,
I am new to this site and I have posted my Ebay Listing Numbers to purchase the plans for a proven, easy to build, lightweight Weedtrimmer Outboard using a 31cc engine. Anything less is fruitless. I spent a fortune in the design of this outboard. Please see the ads, this is your answer to your problems. This is the design evlfkrjohn was referring to. I am a Aeronautical Eng, so I crunched some numbers and created this little monster. It can handle a 24' sailboat with ease and larger, and cost around $ 140.00 to build as "New".
I wish you the very best, please let me know if I can help.
Sincerely,
Dean
jeta2008@netcommander,com

Posted 03-21-2008, 12:31 AM

Hello everyone, I have a time tested proven design that can easily be built just like a brand new outboard for $ 140 - $ 160. I supply parts lists, and the vendors. The plans are easily laid out with drawings, dimensions, and written instructions. After gathering the parts you can build this outboard in 8-10 hours. This is simply the way to go, once you hit the throttle I guarantee you will smile. All "Bugs" have been eliminated, period. A lot of time and money went into the developement to get it RIGHT ! I am selling these plans for $9.95 a set and will be delivered directly to your computer in PDF format, so you can have the plans in a few minutes. Just remit a Postal Money Order for $9.95 made out to R.D. Moss and mail to :

R.D. Moss
261 Julia Circle Apt 15
Sulligent, Alabama 35586

Please be sure to include your email address with your Money Order, as I will send the plans instantly after receipt.

All inquiries please direct to : jeta2008@netcommander.com
1960819608

Posted 04-11-2008, 09:15 PM

Hello Orphaned Cowboy,
I appreciate your criticism, but if you take the time to look at the gear box you will notice the photo you presented is nothing more than a standard weedeater gearbox turning a very small prop. My design is powerful because of the gear reduction, and is equipped with a larger 3 blade Motorguide machete aluminum prop. It is by far superior to the design you have shown, I know because I built this type during the developement of my final design several years ago and found it to be very low on power. Since you have made such an issue over paying $ 9.95 for my plans, I will offer the plans FREE to anyone that wants them just to PROOVE it is far more superior to the other designs. It is FASTER and more Powerful than any design you may have tried. You build it then come back to post your results for everyone to see.
Order the Plans at : jeta2008@netcommander.com

The Plans are FREE, Get them while you can. Alot of time, money and engineering went into this design. It was developed to achieve the maximum performance from the engine. The power is balanced from the engine to the gearbox, and finally to the large prop for a perfect blend of POWER. I am a Engineer so I know what I'm doing. I worked all off the numbers, rpm, gearbox speed and thrust test in a test tank. It puts out 8.8hp at the PROP !
ORDER THE PLANS ! THEY ARE FREE ! I KNOW MY TIME, MONEY AND EFFORT MEANS NOTHING TO YOU ! SO ORDER THE REAL DEAL NOW ! IT'S FREE ! NO MORE COMPLAINTS OK ? I have sold over 1000 of these on Ebay with NO COMPLAINTS - SMOOTHSEAS200

These are his only post and he did nothing but spam his plans in every post, his initial post was nearly 4 years ago, yet in this thread he is new to the site. The guy is an ass, and got pissed at me for calling on the carpet. I could care less for his plans, he can shove up his........

I don't have a degree, but I still have money and time invested in the one I built and I gave it all away for free. Thats the reason I joined this site was because or the free flowing ideas and the willingness to share ideas. I look at thing differently than anyone else would, new eyes, so to speak. We all have a passion for boats or we would not be here wasting hours of our lives yakking it up with each other.

[Orphanedcowboy]

Something struck me as odd:

Hey guys, sorry for the slow response but my computer has been down for a couple of weeks and I've finally got it back up! The design isn't mine, I got the plans from livetofly57 on eBay. The plans came with all the info on how and where to get all the parts needed to do the conversion. It is a very nice design and was very well thought out! My nephew is welding up an aluminum foot for me in the same design as a 40lb motor-guide trolling motor to make another conversion. I will contact the seller about posting the conversion again, I would do it myself but I assured him that I would not expose his idea to everyone. But I can say this much, it has a 4:1 gear ratio that is awesome!

I am not throwing evlfkrjohn under the bus, but he did provide me with a seller name, I searched it and he hasn't sold anything on eBay in the last 90 days, if he worked so hard on the plans and they are so fabulous, why isn't he still selling them?

[*Ender*]

He totally ignored both me and my friend, so it seems he is not willing to do what he promises.

:mad::mad::mad::mad::mad::mad::mad::mad::mad:

Funny, same result here. :mad:

[Mark Wo]

First time poster but I have followed this for quite some time and am nearly done with my weed whacker mud motor.

Anyone kow what kind of gearbox smmothseas200 (Dean) used in his design. I know that the motor I built will work as Ripped off put much time and effort into his and I basically copied this with some of my own modifications. I know that the motor would be much better with a 3:1 gearbox but have not found a way to do this. If I wanted a 1.5:1 gearbox I would just use the gearbox on a brushcutter but there are two things wrong with this - it is only a 1.5:1 reduction and it is then angled into the water. My design is for a mud motor, not an outboard motor.

Any help is greatly appreciated.

Mark W

[superstitch626]

humm i wonder if it would be illegal to post his stuff up on here??? does it have a copy right??? i don't even know post some responses

[Mark Wo]

If the design that smoothseas has is different than what has been posted on here previously, I would not post the info not due to copyright infringement but because I wouldn't appreciate anyone posting plans that I spent some time on appearing on a public forum - just me. Copyrights aren't necessarily applied for and assigned, they are immediately granted to certain items.

If there is nothing new, copyright wouldn't apply and he could be the one in trouble. I would like to kow where a gear reduction could be found for the Ripped Off straight mud motor design. Believe me, I have been searching. I found a 3:1 gear reducer that would fit a Honda GX35 but it was over $100 I think. The whole idea here for me is to homebuild one of these things and do so inexpensively.

Mark

[superstitch626]

dude i was looking on ebay and they have some pocket bike motors with a gear reduction built all ready attached right near the motor

[*Ender*]

dude i was looking on ebay and they have some pocket bike motors with a gear reduction built all ready attached right near the motor

The China gearboxes like the one pictured are 5:1 and reverse the rotation of the engine. Clockwise or RH rotation tends to limit the prop options considerably; but they are cheap!


http://i139.photobucket.com/albums/q282/ender_refuge_photos/2902196632988080_1.jpg

[Guest625101138]

I would like to see the test data that demonstrates a 31cc petrol trimmer motor can develop 8.8HP.

There is plenty of doubtful or misleading information on this site and that is tolerable providing it is not intended to be used in selling something for a profit. I wonder if Mississippi State University knows their name is being used to back false claims regarding test data.

A 31cc motor would need to be supercharged in the extreme to produce 8.8HP. No way a stock motor could do it. Maybe more like 1 to 2HP. Somewhat more than a good rower could pump out but nothing like a rowing 8 could produce and even that is significantly less than 8.8HP.

This site provides detail on small trimmer motor HP:
http://www.alibaba.com/showroom/Weed_Trimmer.html
These are published by reputable suppliers so will need to stand some test of validity. The published numbers are likely to be slightly higher than what is possible because they would not include fan and shaft losses I suspect. Once you add a gearbox they will be even lower.

Rick W.

[John O`Neal]

Stanton inc. offers a 3.1 /1 gear box that fits on most of the engines used on pocket bike, power boards, small scooters,and motorized bicycles.

[kengrome]

The China gearboxes like the one pictured are 5:1 and reverse the rotation of the engine. Clockwise or RH rotation tends to limit the prop options considerably; but they are cheap!How cheap, Ender, and where do you get them? Do you have a link to a source for these items?

I would like to see the test data that demonstrates a 31cc petrol trimmer motor can develop 8.8HP.Don't waste your energy Rick, the guy appears to have posted several lies and now he has conveniently disappeared. Apparently his only motivation is to 'make money' and it seems he will attempt to do so by ignoring things the rest of us value -- like truth and integrity.

[*Ender*]

How cheap, Ender, and where do you get them? Do you have a link to a source for these items?

They run $25-35 bucks +shipping; but I have found them for less at times. Google or search e-bay under "scooter transmission" and you will pull some up with no problem.

The gearbox itself is die cast with spur gears and roller bearings. The unit is sealed with the exception of a vented plug which may or may not need to be addressed depending upon the orientation of the drop in the application. Most I have seen come with a 76mm clutch bell and an sprocket. The sprocket is useful in adapting the splined output shaft to fit various applications; either via chain or by utilizing the hub to adapt to another type connection (turning down the hub and welding part of a deep 8mm impact socket makes a great hex adaptor for 3/8" rod).

[Orphanedcowboy]

I made several runs, and top speed was 3.5 mph on my GPS. I don't know the weight of the boat, but there was a 43 lb battery in the back, a Minn Kota 30 lb trolling motor in there, a cement block(redneck anchor)and my fat azz, 260 lbs worth.The prop is not very efficient, I have several others on the way to test, and I will report back. I couldn't test it on the 14' Alum-weld, as the only aluminum angle I had was not big enough to allow me to C-clamp it to the back of it. I am having to offset plates made to set the engine off the back of the boat about 8", hopefully this will help, if nothing else it will make it more comfortable. Here is the video:

http://i53.photobucket.com/albums/g45/Orphanedcowboy/th_SN850029.jpg (http://s53.photobucket.com/albums/g45/Orphanedcowboy/?action=view&current=SN850029.flv)

Here is my second version:

http://i53.photobucket.com/albums/g45/Orphanedcowboy/SN850443.jpg

Same motor as before, Minn Kota Trolling motor bracket, same type of tiller handle, same prop, and a Expand It Edger attachment

Here is a mud motor style made by Rick Shaw:

Mud Motors by Rick Shaw (http://rickshaw-motors.com/index.htm)

Here is his gear box:

http://i53.photobucket.com/albums/g45/Orphanedcowboy/851743d0.jpg

http://i53.photobucket.com/albums/g45/Orphanedcowboy/39ac8806.jpg

http://i53.photobucket.com/albums/g45/Orphanedcowboy/14bfeb64.jpg

[Syed]

if I post here to sellout something? Is it within the forum rules?

[superstitch626]

Orphanedcowboy,
That video was outstanding!!!!!!! when i get back from Iraq i am soooo making one. tell me what you guys think i bought basically the lower end to a 4-7 hp outboard and i am going to buy a pocket bike from eBay with the gear box already on for like $125 do you think it would be hard to attach the lower end to the motor? here are some pics
http://photos-224.ll.facebook.com/photos-ll-sf2p/v232/150/62/508071224/n508071224_569985_7063.jpg
http://photos-224.ll.facebook.com/photos-ll-sf2p/v232/150/62/508071224/n508071224_569986_7373.jpg
http://photos-224.ll.facebook.com/photos-ll-sf2p/v232/150/62/508071224/n508071224_569987_7632.jpg
http://photos-224.ll.facebook.com/photos-ll-sf2p/v232/150/62/508071224/n508071224_569988_7897.jpg

[Orphanedcowboy]

if I post here to sellout something? Is it within the forum rules?

I re-read the forum rules and see nothing stating it is against the rules peddling your wares, you may need to contact a forum moderator first and get clarification to be sure.


Orphanedcowboy,
That video was outstanding!!!!!!! when i get back from Iraq i am soooo making one. tell me what you guys think i bought basically the lower end to a 4-7 hp outboard and i am going to buy a pocket bike from eBay with the gear box already on for like $125 do you think it would be hard to attach the lower end to the motor? here are some pics

Superstitch here is a picture of badges65 lower unit conversion:

http://www.boatdesign.net/forums/attachment.php?attachmentid=511&d=1054788903

His post is back on page one of this thread, I don't think he did anything other than mount the engine to the lower unit. Your gear reduction is already uilt into the lower unit. You can get your ratio by turning the input shaft one rotation and count the number of output shaft rotations.

As far as Smoothsea200's plans, his gear box is a modified trolling motor lower unit with a 4:1 gear reduction. His claim of 8.8 hp and the ability to push a 24' plus sailboat with ease are a little exaggerated . I will follow up with his plans and address each of his claims accordingly. First thing he states is HP, which cannot be measured accurately in a application with either a centrifugal clutch or a constant velocity transmission.

Once I have completed my term paper on horsepower, which you will get a kick out of how that term was coined, thrust, torque, and application efficiency, I will post them here. He has mislead just a few people, some of which have no clue they have been scammed.

[dragonjbynight]

I know there are many people on here who use trolling motors. One of my several crazy off the wall ideas, stemming from having to paddle back in when the battery dies is using the weedeater with a car type alternator to provide supply power to the trolling motor. (kinda like a train, diesel generator providing power to the electric motors that move it). What do you think, would it be feasable? I was thinking ridding it of the shaft and placing a pulley or gear at the end, mounting it and either using a short chain or short run v belt between the two.

Would have applications beyond just trolling motors though, any 12 v lighting, sound or otherwise central low voltage system could theoretically be utilized by it.

The only issues i can think of would be whether the draw would be too much or if a pulley system can be mounted to the shaft without too many problems.

[Guest625101138]

You could just carry another fully charged battery given the weight of the motor and generator.

Another alternative is to get a low cost multi-meter and monitor the battery voltage under normal load conditions. Do a discharge test recording battery voltage against time. Under relatively high load the voltage will droop noticeably so load voltage is a good indication of state of charge. Should start with about 12.4V (or multiples of it). By the time you get down to 11.4V you will be running out of puff. Should not go below 10V. The voltage will have some variation with temperature but not enough to cause great errors from week to week.

A third alternative is to buy a portable generator and take the battery charger with you. These are low cost items and save a lot of effort in mounting a motor to an alternator.

If you must use the alternator then look to direct couple rather than use belts or chain this will avoid radial load on the tiny motor shaft. The alternator is designed for belt drive but the motor isn't. You can get scooter motors that have a chain and this would be slightly better than a belt.

Rick W.

[crokseti]

Could there be any risk from electrical shock?

My project is finished except for the old Ryobi not wanting to stay running long enough to test out on the water.
I obtained another to get carb parts off of but overtime and other life issues interfered so I havnt had time to tinker.

[masalai]

So long as the regulator is working (integral to the alternator) and power is used to charge the battery (give the alternator a suitable load so the voltage does not "run away" - and put your tongue on pos & neg to see if the voltage is too high (don't want to burn out the drive motor).... he he he

[Orphanedcowboy]

Sorry work has kept me busy, I need to get back to the plans and finish the post. I plan on building one of his motors as well, but it will be far more costly than he claims, the gear set was well over $75 even with our corporate discount, and trolling motors that are burnt up are worth more as parts than a new one, so I just bought a new for $80 to use as my donor for this exercise.

[superstitch626]

Orphanedcowboy you make me laugh man. going as far as to build one of his design to prove him wrong. but what ever post up the build when you get a chance.

[Orphanedcowboy]

It's not really to prove him wrong, it is a well thought out design, I am building it to prove to him it isn't as efficient as he claims, or as cost effective. Since he won't come back and post video of the design pushing a 24' sailboat or any large boat for that matter, I will, and if I am wrong I will admit to it, but I think we all know what the outcome will be.:D

[smoothseas200]

Well by reading the threads most of you are unhappy with me, I got off on the wrong foot with OrpanedCowboy when I was new to this site. As far as breaking any promises for sending the plans for the outboard, well I do apologize for that. My area was hit very hard by tornadoes and knocked out everything. Today, May 12, 2008 is the first time online for me since the twisters hit. I really cannot believe some of the harsh words and criticism that have been posted in reference to me.

I am and have always been a man of my word. Thank you to those that posted threads of kindness and understanding. I now have a new more reliable internet service, and will be more than happy to send the plans to you. My New Email Address is : allaerotech@centurytel.net

In closing, my family and I lost everything we had. We were very lucky not to have been home at the time or it could have been much worse. I wish the very best to everyone, and I am only here to help you if I can. Please write, I'd like to hear from you.

Sincerely,

Roy :)

[Orphanedcowboy]

Well by reading the threads most of you are unhappy with me, I got off on the wrong foot with OrpanedCowboy when I was new to this site. As far as breaking any promises for sending the plans for the outboard, well I do apologize for that. My area was hit very hard by tornadoes and knocked out everything. Today, May 12, 2008 is the first time online for me since the twisters hit. I really cannot believe some of the harsh words and criticism that have been posted in reference to me.

I am and have always been a man of my word. Thank you to those that posted threads of kindness and understanding. I now have a new more reliable internet service, and will be more than happy to send the plans to you. My New Email Address is : allaerotech@centurytel.net

In closing, my family and I lost everything we had. We were very lucky not to have been home at the time or it could have been much worse. I wish the very best to everyone, and I am only here to help you if I can. Please write, I'd like to hear from you.

Sincerely,

Roy :)

Let me be the first to say I am glad you and your family are okay, material items can be replaced, family cannot. If there is anything you need, just ask.

[smoothseas200]

* Please Note * The outboard will cost more in todays dollars. As indicated on the plans it was initially designed and tested in 2004, so this cost was significantly less. Please pardon my mistake at the time of posting. Also to clarify, the claim of 8.8hp at the prop was calculated in the torque value. The speed won't make your eyes water, but it has broken the transom on some aluminum boats. It will push your large sailboat with ease and at a safe speed. -Roy

[superstitch626]

Roy,
i would also like to say that deep down i am sorry for your losses. on a better note you have one fan :)
V/R
your buddy in Iraq
Evan

[smoothseas200]

Thank you very much OrphanedCowboy for your very kind words, that alone is enough for me. Do you have my plans ? If not, kindly forward your email address and I'll send them right out to you. Once again, thank you very much for your kindness and generosity. I did try to post the plans but the meter indicates I exceeded the limit by 2.57mb so therefore it would not post. Man, I know we are all brothers in this thing and it's up to us to make the best of it. I apologize if I have ever offended you in any way. Let's start it all over shall we ?
Very Sincerely,
Roy D. Moss

[smoothseas200]

Evan,
Such kind words coming from you, a man in Iraq directly in the danger zone fighting for our country. You face danger 24 hours a day. I just don't know what to say other than God Bless You my friend, stay low and stay safe until we can get you home. And above all, if you ever need anything even just to write buddy you just let me know. If God doesn't take me out of here, I'll always be here for you. Take care my friend.
Very Sincerely,
Roy

[smoothseas200]

I'll try to post my plans again. They are in PDF format so you should be able to print them easily. Please note the date on the plans. (2004)
21382

[robrohdeszudy]

To Roy: glad you and yours are OK after the storms. Thanks for posting the updated plans. I bought a set from you via Ebay a while back, but I've stalled d/t the gearing cost. My boats are light enough taht I can probably do the longtail version.

To All: anyone seriously particilating in this thread should probably go to the library and check out Dave Gerr's Propeller Handbook. It tells you all about how to calculate things like how fast a given weight hull can move with a given hp, and the prop dimensions needed based on shaft rpm. Handy stuff!

Essentially Roy's setup with the reduction gear lets you run a bigger prop, which gains you more efficient operation, and more real-world thrust at low speeds. It does not gain you 8 hp - Roy calculated that wrong, but it should get you low speed thrust more or less like what you'd get with an 8hp motor without gear reduction.

If you do the math in the Gerr book, you can see that a 3" prop will let a weed whacker turn to its full rated rpm. Pitch would be governed by how fast 1 hp can push your boat. But it would have to be pretty flat for sure. This tiny prop would have a lot less thrust and be less efficient. It would have a harder time pushing you against a headwind, for example. It might even be better to throttle the motor back and sacrifice some hp to get lower rpms and run a bigger prop, but this would depend again on what you're pushing.

Here's an extreme example - suppose you used the gearbox from a Mantis tiller. That 240 rpms would let you swing something like a 22" prop! (That's from memory, but I know it was really big.) Still only 1 hp, but using it to make a *wall* of slow moving water rather than a tiny stream of fast moving water.

Seriously, read the book. This stuff is engineering, and that's no place for wimps! The math is simpler than it looks, and once you get it you can do a whole lot.

The short story is to use Roy's plans if you need lots of thrust (e.g. superstructure catching air or a big boat), and use something like ripped off's longtail for a small, light boat with not much weight in it.

Best,
--Rob

[robrohdeszudy]

Here's some math for y'all. Suppose your boat can be driven to 4.75 mph with 1 hp, which I'm assuming a weedeater makes at 7000 rpm. All these are for 2-bladed props. Here's what the calcs tell you:

7000 rpm (1:1) - 3.12" x 1.92" prop (not much prop surface area here)
3500 rpm (2:1) - 4.73 x 3.81" prop (Already WAY better)
2800 rpm (2.5:1) - 5.41 x 4.81" prop
1750 rpm (4:1) - 7.17" x 7.7" prop (this is the Lil' Indian ratio)
1120 rpm (5:1) - 9.37 x 12.03 prop (getting steep, I wonder if it would start well from a standstill)

Notice how the 4:1 ratio gives you close to a "square" wheel - e.g. diameter and pitch about the same? There's nothing magical about this, but it is an indication that you're somewhere in the reasonably efficient range, ASSUMING those numbers are indicated by the formulae. Arbitrarily using a given prop will get you the problems that others have found, like stalling or lack of thrust.

--Rob

--Rob

[timmytim]

I am looking for a small/inexpensive 4 cycle outboard to push a 20'(1350 lb) sailboat just far enough away from the dock on an inland lake so that I can put the sails up.

I have researched this website and others for the last two days for answers but I am still confused.

Do you think the following setup would push my boat approx. 2-3 mph?

Troybilt TBP6160 32cc weed trimmer and some type of prop(I would have NO idea as to which one to use or how to attach it)

http://www.troybilt.com/webapp/wcs/stores/servlet/product_10001_14102_496547_55009_-1

Would there be a noticeable difference in power if I went with the 29cc version vs the 32cc version?

The engine will probably have to be positioned in such a way that would not be the normal cutting position and I was wondering how this would work as far as gas to the carb and oil lube. Also, would I just attach the prop and pack the shaft with grease?

Thanks,
Timmytim

[wac m trac m]

Howdy, I,m new on here. Getting ready to build a small longtail moter. After reading all these posts I think I'm going to try a small moter instead of a weedeater conversion. Heres a deal I found
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200333569_200333569

Tecumsuh 3.5 hp for 100bucks.

I know it's kinda pointless to have more hp since my boat wont get on plane but I figure with the right prop I'll be able to load the boat down and still reach max speed around 8mph.
My question is where can I get a simple gearbox simular to RickShaws'? I'm going to take ripped off advice and go with a 2:1.
thanks

[smoothseas200]

Hello everyone ! I found a small prop in my collection of toys that would work great for a weed trimmer beavertail conversion. The dimensions are :

Main diameter is : 5 3/4"

Shaft diameter is : 3/8"

I don't know what the exact pitch is, but I made about 15 other beavertails for other people and the 31cc weed trimmer engines I used worked very well. The engine did not bog down, and pushed very well. I added a skeg on the bottom of the shaft placed down near the prop. These things are great for 8' - 10' boats. Duck hunters, this is the cats meow !

I will send the new prop free if you need it, just pay the shipping. Contact me at : allaerotech@centurytel.net

I'll be happy to help out any way I can, I have designed, built and successfully tested so many different weedtrimmer conversions you would not believe it, and spent several thousand dollars doing it to get them right. It almost cost me a wife. This knowledge can be yours just for the asking.
Take care everyone. :)

[John O`Neal]

This little motor will get it done without a gear reducer. No bog whatsoever. All I had to make was the bushing/seal on the prop end and bend up the handle out of .750 od .125 wall alum. tubing. I used a trolling motor mount to attach it to the boat. It uses a 52cc Chinese made brush cutter. $179 new. I tested it on my 13/6 " 4 rivers total wgt. 320 lbs. The motor pushes the boat with ease and the conversion was so simple even a caveman could do it. The prop is a Young`s T-12. I had one so I just put it on and hoped . It works great.

[wac m trac m]

Looks good John, where can I go to get a power head like that?

[wac m trac m]

Heres what I made so far. It works in a tank but I haven't put t in water yet. I used a briggs and stratton 34.5cc moter. It was tough though cause the shaft tapers down to 7/8's and I already welded a 1inch shaft so I grinded alot and made it work.
I finished the throttle cables since these pics were taken. All I have left is the boat mount. I'm doing one like ripped off made since I dont have an old trolling moter.

http://www.hunt101.com/data/500/DSCN0876.JPG





http://www.hunt101.com/data/500/DSCN0877.JPG

[John O`Neal]

The unit seen is marketed in the U.S. by Duropower.com it is their 52cc 2 hp brushcutter. It lists for 179.00 but they really lug you for the shipping. The engine is a Chinese built unit that they build by the thousands. They are used a lot on scooters , power boards .Go carts, pocket bikes, and ATV`s. You can find new motors offered on Ebay , Ebay express, and by doing a scooter parts search. There is a lot of aftermarket performance parts available for these motors to improve their power output. I spent about $30 on mine for a velocity stack, hi-performance air filter and a rocket key(wood ruff key) that advances the timing 10 degrees. It really brought the little motor to life and improved the low rpm torque. A very easy modification. I just received a new motor I purchased on Ebay Express to build my hunting buddy a mini-longtail. It came with an electric starter and a 5/1 reduction gearbox. It cost $145.00 delivered. Were going to try to run the 5/1 reduction and pull a 10 1/2" prop. Nice job on your unit. Let us know how it works in the water.

[freakasis]

why has no one used an edger shaft to get the 90 degree bend? like the ones on an echo...they also can be mounted to bigger echo engines easilly.

[wac m trac m]

I would try that if I was making an outboard type moter but here in the Texas hill country I hunt/fish rivers. The Blanco and Guadalupe are limestone rivers and the depth changes alot. You even have to get out sometimes and drag your rig over a dam or shallow area. With a longtail you just hold it where it clears and go.

[wac m trac m]

Hey John, got my moter mount done last night. I will be trying it out in the water today. I have a question for you though. Does your moter have a clutch? Mine is really tough to get out so I left it in there. Most people seem to pull them out cause they burn up easily from the water load.

[John O`Neal]

The motor has a much larger clutch than a weedeater type, 78mm. This type of clutch has replaceable clutch shoes $15 and locks up at 2500 rpm. It is nice not to have the prop turning when idling. The clutch pictured on the Brushcutter motor is from a 31cc Ryobi. Here are a few additional pics of the motor in its final configuration.
http://i259.photobucket.com/albums/hh310/JohnLOneal/longtailAugust08002.jpg
http://i259.photobucket.com/albums/hh310/JohnLOneal/longtailAugust08006.jpg
http://i259.photobucket.com/albums/hh310/JohnLOneal/longtailAugust08005.jpg
http://i259.photobucket.com/albums/hh310/JohnLOneal/longtailAugust08004.jpg

[wac m trac m]

Took my boat out and it did great. There moter RPMs were perfect for the prop. No cavitation. I ran with GPS in hand and she did 8mph in about 40 yards. My bracket started slipping from the vibration and the gear oil in the shaft started leaking. I got a few bugs to kill but she works great. At 1/4 throotle she runs real smooth and easy. The moter seems to purr at that rpm. It does 5mph like that.

I'll post pics soon. I need a better bracket. Mine lets the moter sit way to deep when I'm not holding the tiller.

[John O`Neal]

Wac m ; Glad to see that you motor worked out so well. The problem you reference regarding your mount allowing the motor to run to deep can be addressed by putting a limiter on the mount . Turn 4 fun has a design, posted earlier in this thread . I have an adjustable limiter on the trolling motor mt. that I used. It is that star shaped handle and threaded rod shown in the pic of the mount. Good job!

[ripped off]

Hey smoothseas, are those your plans I'm seeing on ebay?

[ripped off]

Ah yes, they are your plans. So the question that begs to be answered is this. Why after bashing my little motor several pages back while shouting your own praises as an areonautical engineer who knows what he's talking about, why are you now using a picture of MY motor as the gallery photo in your ebay ad???? I think OrphanedCowboy had your number right from the start. You tried to deceive people with your bogus claims of 8.8 HP from a 1 HP motor and now are trying to deceive people into thinking they are getting plans for MY motor (which I already gave out for free) all while still claiming 8.8 HP. Dirty pool mister. I demand you remove pictures of my motor from your ebay ads immediately and stop trying to use my reputation as a way to trick folks into buying your plans.

Heres a link to one of his ebay ads for the rest of you to see.

http://cgi.ebay.com/ebaymotors/PLANS-BUILD-YOUR-OWN-OUTBOARD-TROLLING-MOTOR-UNDER-200_W0QQcmdZViewItemQQ_trkparmsZ72Q3a552Q7c39Q3a1Q7c66Q3a2Q7c65Q3a12QQ_trksidZp3286Q2ec0Q2em14Q2el1318QQhashZitem330257792737QQitemZ330257792737

I may be way off base here but if I'm a person who has never been to this forum I'm gonna read that ad and look at that pic and think thats the motor I'm buying plans for. And if I'm a person who frequents the Refuge or Duckhunting Chat or several other websites where my stuff is posted, or has ever google searched "weedeater boat motor", I'm gonna recognize that little yellow motor as being associated with Ripped Off AKA Turn4fun, AKA Lying In Wait and then MY reputation will be tarnished when someone builds a 1 HP motor that is nothing more or less than a 1 HP motor thinking that they are getting almost 9 HP.

[wac m trac m]

Wow that stinks. Smoothseas did me right and sent me a prop for free. I cant use it though cause it is for a moter with a gear reduction. My set up would turn it the wrong way.
I dont get why He wouldn't just give up on selling plans for the moter. He already gave them away for free on here.

Ripped off, it's sad to see you've been done wrong. I have alot of respect for you. If it wasn't for your plans on here I wouldn't have what I built. I appreciate you generosity in putting your plans on here. I pretty much built a moter like yours but changed a few things. I have a few questions.
I used gear oil in my shaft and it leaks when the prop spins. Have you had that problem? I'm going to try tapping the aluminum tube for two grease fittings on each side of the center bearing and fill it with marine grease.

My other question is have you ever had problems with the mounts, handle bar and moter mount moving from the vibration? I grinded my shaft myself cause I couldn't find any machine shops in my area to do it. I did ok but when the shaft gets to spinning theres some decent vibration. What did you do to fix the problem?

Thanks again for your ideas. I appreciate your help. Your invited to Texas duck/deer/ hog/ quail/dove/ turkey anytime if your interested. Email sent.

[ben2go]

What about something like this using a weedeater engine or small mower engine instead of an electric motor.Read through the additional specs and photos for a better idea how it mounts and operates.
https://www.boatdesigns.com/products.asp?dept=474

[hallsj]

Here is mine.
http://www.youtube.com/watch?v=xM6bBX4XZcc

[smoothseas200]

Hello Ripped Off -

Those are NOT my ads on Ebay. I haven't been selling on Ebay for quit some time now. It could be someone that bought the plans a long time ago from me, and decided to sell them hiself. I don't know, but they are definitely not my ADS ! I suggest you take it up with that person and quit slamming me for everything. I posted the plans here on boat design for everyone to use and enjoy, free.

Hello wac m trac m -

Happy to hear you recieved the prop. Sorry it would not work for you. I stopped selling on Ebay simply because I got tired of keeping up with it, and the ad fees / Paypal fees kept going up. That's the whole story. Ripped Off is posting someone elses Ebay ad. It isn't mine. Why would I give them away here then turn around to pay ad fees to sell on Ebay ? That doesn't make a damn bit of since. Take care !

Ripped Off -

Why don't you ask this guy where he lives ? I'm in Alabama, I doubt he is. And another thing, if I said something out of line in regards to your outboard I apologize. It was wrong of me to do that. Do try to find out who the guy is selling plans with a picture of your motor. I saw the ad and read it. It is almost a word for word copy of my ad. That pisses me off.

You know, there is too much trash thrown around at each other on this site. If that time was spent developing newer and better designs this would be a better place. You guys take care. This is my last post, I will not be back.

- smoothseas

[ben2go]

Is there a ready made prop that will work for these conversions?Plans for building one?I would like to be able to buy one or make one without having to track some individual down and beg for one.Our lakes and rivers are shallow and I will probably break or knock a prop off.

[wac m trac m]

Ok mines almost done. Took it out on the Colorado river today and went catfishn it did great. Tops out at 8mph even with all the gear in the boat. I still need to fix the tiller. I mounted it to far back so the moter trys to dive and it's hard to keep it up on the surface. Which is another problem. I need to make a new mount. Almost there.
http://www.hunt101.com/data/500/medium/DSCN0882.JPG




http://www.hunt101.com/data/500/medium/DSCN0878.JPG


She loads up nice. The moter swivels around like a beavertail type moter.
http://www.hunt101.com/data/500/medium/DSCN0883.JPG

[kengrome]

Thank you very much OrphanedCowboy for your very kind words, that alone is enough for me. Do you have my plans ? If not, kindly forward your email address and I'll send them right out to you.Sorry for your loss Roy.

I never got the plans you promised either, maybe you can send them to me too. My email address is bagacayboatworks <at> gmail <dot> com

:)

[John O`Neal]

Smoothseas : Sorry to see you call it quits. The forum can use all the diversity of ideas it can get. It keeps it fresh, productive and interesting. I downloaded your plans and I think your design is unique in every respect. I am at a loss to understand the resentment displayed because you marketed them on Ebay. I don`t see how they possibly infringed upon anyone else`s design. It appears, based on addresses, that someone else has pirated your plans and has created quite a stir. I hope you will reconsider leaving the forum.
Ripped off ; I think I would be flattered if someone used a picture of a motor I built, but I understand your position if you think the seller was intentionally trying to deceive potential customers and pass it off as his own design. I have included a pic of my buddies Island Hopper mounted on a foam boat we built this summer. It looks a lot like your motor . He has had it for a number of yrs. King Crawdad Motors is also making a version of the gear head style conversion utilizing Stihl brushcutters as the donor unit. I guess the point being. It is the rare exception, that our ideas in this field are totally exclusive. Please keep up the good work, your designs and fabrication techniques have helped a lot of us out here.

[wac m trac m]

Cool pic John, that's a good looking unit yall made. Is that a K&N filter on there?

Also is that the original shaft from the weed eater?

[ben2go]

Cool pic John, that's a good looking unit yall made. Is that a K&N filter on there?

Also is that the original shaft from the weed eater?


I am curious also.I am trying to find a shaft and prop that will work on my Homelite.I have a 30cc with the curved shaft and centrifugal clutch.Purdy strong little engine.It spun one of those large Gator heads with the nylon blades.

[John O`Neal]

Wac M ; The motor started life as a brushcutter with a 5/16" drive shaft, splined on both ends. The remanufacturer "Island Hopper" shortened the boom then cut a section out of the drive shaft. They welded it back together retaining the drive splines on both ends. Ingeniously simple. The air filter is a K&N style washable element. I choose not to oil it since I would be operating the engine in an over water environment only. Glad your mini-longtail works so well. I`m sure your going to have a great time hunting with it this season. Good job!

Ben2go : I would suggest you try (WWW. Youngs die cast aluminum props.com) I am sure you will be able to find a suitable prop for your project. They have numerous props in the 5 1/2" to 5 3/4" range that should work on a weedeater powered direct drive unit. As far as drive shaft material. Either 5/16' or 3/8" stainless steel rod will work well. Go back to the start of this thread and read the postings . There are some great construction methods discussed some with meticulous instructions and material lists. Ripped-off has a great one that will help you through the building process. Good luck with your build !

[*Ender*]

John-

Nice rig!

In looking at pictures, you still have the exhaust in the original location (now blowing at your head). I have a similar looking 43cc China engine and found it very easy to convert the stock exhaust to the opposite side. As a bonus, from there you can also easily add a secondary muffler to further reduce the noise. If you are interested let me know and I can shoot you some instructions and pics.

Ender

[John O`Neal]

Ender; I am always interested in a better way to build the mousetrap. You are absolutely correct. I should have moved the exhaust outlet to the other side of the muffler. I had every opportunity to accomplish this when I opened up the muffler to improve the flow. The muffler looks stock from the outside but has been relieved. The stock muffler is a two piece unit, flanged together . I heated the flange and folded it back separating the two halves. Inside is a baffle plate separating the two halves with 4 or 5 (5/16") holes in it. I tripled the number of holes in the baffle. I then drilled out the tiny outlet pipe and replaced it with a piece of 1/2" EMT tubing. Hi-performance billet alum mufflers are available with the outlet on the other side but they want a $100 for one. I thought that was a bit steep.That's almost as much as the motor cost. I would be very interested in the muffler info. that you have and would sincerely appreciate it, if you feel like sharing.
John O`Neal

[wac m trac m]

Thanks John, I took the boat out this morning and it ran great. I think I want to raise it a bit so it's easier to steer. I looked on the turn for fun website but couldn't find to part about the trollingmoter mount that you mentioned earlier. I found a replacment moterguide one for 60 bucks but I know theres got to be a cheaper way. I'm going to hit a garage sale in my hood today.
Looks pretty cut and dry...just clamp it on. What is the screw in the back for?

[*Ender*]

John-

I did not get nearly as involved as you with the muffler, but the result was pleasing none the less. The pictures pretty much tell the story with the two exceptions:
1- Ensure the outlet location leaves enough meat in the plastic muffler cover maintain its strength.
2- Secure nuts w/ integrated metal lock washes to the interior with krazy glue to aid in assembly of new outlet.

http://i139.photobucket.com/albums/q282/ender_refuge_photos/100_3108.jpg
http://i139.photobucket.com/albums/q282/ender_refuge_photos/100_3109.jpg
http://i139.photobucket.com/albums/q282/ender_refuge_photos/100_3103.jpg

[John O`Neal]

Wac m ; The small thumb type screw locks the motor in the mounted position when tightened. If you loosen it you can lift the motor out of the trolling mtr. mount and the mount will stay on the boat. The star shaped knob adjusts in or out to set the max depth the prop runs at.
The motor mount designed by Turn 4 fun aka Ripped -off can be found earlier in this thread . In his post he outlines construction methods and provides a material list. I am constantly on the lookout for old trolling motors . They not only provide a source for mtr. mounts but often have usable props. I bought an old Shakespear Trollmaster 624 for $15 sat. It had a 5 1/2" composite prop and a good mount. Got lucky to find it so cheap.

[lasportsman10]

Hey man,
Just built a boat around high performance weed wacker engines. uses two 25.4cc 2cycle gas engines(3.5 HP each) and mini jet drives (I ould only get 1/3 throttle and about 12 mph out of my old canoe before air was forced into the jets and they would cavitate, wrong hull shape). MANY other mods to be put on the web later as I am 4 days away from the maiden voyage/christaining.

HINT to use an el cheapo gas engine you will need a clutched model (more torque ) and you will need to mount your engine in the boat through the hull and use a "stuffing tube filled with grease" or figure out a way to seal the shaft or the rotating flex shaft will draw water up the pipe and all over you and your boat/engine. So far as the prop is concerned I started out using a 2.9" RC boat prop (I think it was called a prather 275) and with a single 30cc john deere with a clutch I was able to go faster than paddling with 2 people and gear in the boat!!

Belive me I have been wasting $ on this project for 3 years and KNOW what I am talking about!!! The el cheapo engine can be done if you follow my advice and for about $250 smackers using NEW equip. a good tuned/muffled pipe to keep the racket down will cost ya though.

Feel free to contact me degreeoff1@yahoo.com

good luck

do you have any pics of the boats or motors? if so email me at mporche10@cox.net

[ben2go]

Here is my plan.Please advise me if there is something wrong or can be improved.I have a 30cc Homelite with a curved shaft.My idea is to build an out board.I wanna eliminate the curved shaft(ebay for extra $$$),build a straight shaft with a gear head off of a straight shaft weed trimmer.May be able to use the lower shaft and gear head off a trimmer made for attachments.I wanna cut and use the line shield as an anticavitation plate.I am doubtful about this working.I like the idea mentioned earlier about using copper pipe and fittings to get the exhaust in the water.Noise is a concern in my area.One place I will be is a private lake.1 question I do have have, is there a edger or other gear head that will provide some gear reduction?I haven't found a clear anwser to this question.My thoughts on the edger maybe having a gear reduction is due to additional torque needed to spin a blade.Any ideas or suggestions?I plan to do this soon if I am able to finish building my Jon boat.

[John O`Neal]

Ben; What you are desiring to do is quite feasible. Turn 4 fun aka Ripped -off (try a Google search) has a step by step tutorial on how to build a out board style unit using a 2 piece straight shaft boom. A pic of his motor can be seen in a entry earlier in this thread posted by Orphan cowboy. Caveman has a picture of a copper, underwater exit, exhaust system, also earlier in the thread.

[wac m trac m]

I found a decent moter on the duropower website. If you go to the website and look under engines. You can find a 51.7cc moter for 119.00 and 20 bucks for shipping. You just buying the power head.Thats a great deal. I wonder if it comes with that nice metel cowling where it attaches to the drive tube like on Johns moter..or a clutch? You may have to buy the brushcutter to get them but then you gotta pay 70 more dollers for shipping..ugh.

[wac m trac m]

Heres a link to it.

http://www.duropower.com/item.asp?PID=86&FID=3&level=1

[wac m trac m]

Theres also a nice looking 4cycle for a decent price in there. I wish I knew if they have a clutch. John do you know if you can get parts forthese engines pretty easy?

By the way Ender, looks like you have something cool there. Lets see the whole set up.

[John O`Neal]

Wac m ; The motor you are looking at comes with the clutch shoes on the motor. I doubt it has the clutch drum. Duropower has the parts you reference in a drive shaft kit unit. I don`t know the cost. The engine you ask about is probably the easiest engine of this type to get all kind of parts for . The Chinese must be building millions of them and importing them all to the U.S.A. I have seen them sell for as little as $99 with free shipping.
Note of interest; You will see this engine often listed as 49cc by the Internet vendors and scooter manufacturers . They are actually the same eng. as the 52cc . If a scooter has a motor less than 50cc it doesn`t require a license in most states. So everyone lists them at 49cc.

Ender; Nice job on moving the muffler outlet, looks like a factory job.

[ben2go]

Ben; What you are desiring to do is quite feasible. Turn 4 fun aka Ripped -off (try a Google search) has a step by step tutorial on how to build a out board style unit using a 2 piece straight shaft boom. A pic of his motor can be seen in a entry earlier in this thread posted by Orphan cowboy. Caveman has a picture of a copper, underwater exit, exhaust system, also earlier in the thread.

Yea I seen all of those.I went to strip the old Homelite and realized it's a 25cc.I guess my old Ryobi was the 30cc one.I let someone talk me into locking out the clutch on it instead of replacing the drum and shoes.Got into some deep grass and blew $250 to find a property pin.When I was using it in knee high grass, in a drainage ditch,I hit the property pin wide open,and tossed the rod and crankshaft through the engine case.I was angry for weeks over that.So I bought the Homelite for nothing at Lowe's.







I had another idea :idea: Scary ain't it.I thought about obtaining a non running 1 to 7hp outboard or complete foot.Then stuff my 3.5hp Briggs N Stratton on top of it.I have a spare push mower that's willing to donate it's heart.Ahhhh!Gotta do something soon.I will be ordering my epoxy and paint for my Jon/Punt.In 2 weeks I hope to be doing a little pre fall bass and crappie fishing with my 2 sons.

[Big Mark]

Hello,

I just signed in, after finding this forum on Google. I've been interested in the idea of converting a weed eater motor to an outboard for some time, I guess ever since I came across an item on Ebay which advertised a do-it-yourself set of plans to convert a typical 25cc weed eater into an 8.8 hp outboard. I purchased the plans from a seller who went by the name of Masterplans, and have since received and reviewed them, and to be quite honest it all seems very interesting. But, thus far I haven't yet given it a try. I have no way of knowing if these plans are legit or not, so I'm following this forum closely to see what other information I can obtain.

I do have a few questions though, I'm just curious.

1) I wonder why someone would even try to convert a weed eater motor into an outboard if you can find so many used 1.2 - 5 hp motors on Ebay for a good price, i.e. Eska, Tanaka, etc. I just recently purchased a used (very good condition) Eska 2 hp motor for $100.00, and it should push my 14ft. inflatable pontoon boat just fine. These are all great little, light weight motors, many with Tecumseh power heads, that burn little gas. Is there a reason why you don't refer to these types of motors?

2) If one wanted to convert a motor wouldn't it make more sense to purchase a motor like one of these http://www.smallenginesuppliers.com/shop/html/pages/briggs_vertical_shaft_engines.html or http://www.smallenginesuppliers.com/shop/html/pages/tecumseh_vertical_engines.html. You can find some very lightweight Briggs & Stratton or Tecumseh motors for not much money. Wouldn't these motors be more suitable for this type of work? Some, I know, weigh more than weed eater motors and cost more, but wouldn't they still work? Here's a 2 hp Tecumseh that weighs only 7 lbs. http://www.smallenginesuppliers.com/shop/html/pages/products/tecumseh_vertical_engines2002.html

Anyway, thanks for all your posts. I look forward to visiting this forum. While my Eska should work fine, I'm always open to new ideas, especially if it gives me the excuse to work on a new project.

Regards,

Big Mark

[Guest625101138]

Hello,

I just signed in, after finding this forum on Google. I've been interested in the idea of converting a weed eater motor to an outboard for some time, I guess ever since I came across an item on Ebay which advertised a do-it-yourself set of plans to convert a typical 25cc weed eater into an 8.8 hp outboard. I purchased the plans from a seller who went by the name of Masterplans, and have since received and reviewed them, and to be quite honest it all seems very interesting. But, thus far I haven't yet given it a try. I have no way of knowing if these plans are legit or not, so I'm following this forum closely to see what other information I can obtain.

I do have a few questions though, I'm just curious.

1) I wonder why someone would even try to convert a weed eater motor into an outboard if you can find so many used 1.2 - 5 hp motors on Ebay for a good price, i.e. Eska, Tanaka, etc. I just recently purchased a used (very good condition) Eska 2 hp motor for $100.00, and it should push my 14ft. inflatable pontoon boat just fine. These are all great little, light weight motors, many with Tecumseh power heads, that burn little gas. Is there a reason why you don't refer to these types of motors?

2) If one wanted to convert a motor wouldn't it make more sense to purchase a motor like one of these http://www.smallenginesuppliers.com/shop/html/pages/briggs_vertical_shaft_engines.html or http://www.smallenginesuppliers.com/shop/html/pages/tecumseh_vertical_engines.html. You can find some very lightweight Briggs & Stratton or Tecumseh motors for not much money. Wouldn't these motors be more suitable for this type of work? Some, I know, weigh more than weed eater motors and cost more, but wouldn't they still work? Here's a 2 hp Tecumseh that weighs only 7 lbs. http://www.smallenginesuppliers.com/shop/html/pages/products/tecumseh_vertical_engines2002.html

Anyway, thanks for all your posts. I look forward to visiting this forum. While my Eska should work fine, I'm always open to new ideas, especially if it gives me the excuse to work on a new project.

Regards,

Big Mark

Mark
The fellow that offered the plans has posted on this thread. If you go back you will see the notion of getting 8.8HP out of a 25cc weed eater engine is nonsense. Maybe somewhere between 1 to 2HP.

I think the popularity of weed eater engines is their availability and the fact that there is already some sort of extended shaft mounted to the motor. You can go down to the local hardware or maybe even have one that is sitting in the back shed doing nothing. Buying a stand-alone motor takes more effort unless you are a regular internet shopper.

Getting the best from any motor is a matter of prop selection and then matching it to the motor. A big slow revving prop with 20:1 gearing could pull a tonne slowly. A 3" prop could push a large model boat at maybe 50mph. A small diameter shrouded prop will do better than an unshrouded prop of the same diameter if high thrust is required.

Rick W

[ben2go]

I am hoping to pick up a Gamefisher outboard with a bad power head and replace the power head with a Briggs N Stratton 3.5hp vertical shaft push mower engine.The lakes in my area just recently banned 2 stroke engines and they're inspecting engines before they enter the ramp area.

[redtech]

ben2go, about the lake that banned 2 stroke, what lake and what technology of two strokes were banned, for some two strokes are cleaner than a four stroke
being from CA i've found even the tahoe region engine bans to be a joke at times
example:new technology two strokes only if not on a sail boat (still running a 1976 six horse johnson when i go there no complaints)

[Big Mark]

Hi,

is this the type of Briggs & Stratton motor you are referring to? http://www.smallenginesuppliers.com/shop/html/pages/products/briggs_vertical_shaft_engines4299.html

I wonder how difficult it would be to mount it onto an outboard casing?

Regards.

Mark

[alexlebrit]

Just a quick though and I don't know if it's been mentioned already somewhere deep in a post, but - pollution.

Is it that good an idea sticking a 2-stroke motor's exhaust pipe in the water and leaving a nice oily trail? I know in France they'd have you torpedoed - 4 stroke only here.

[John O`Neal]

Sometimes a picture will suffice for a thousand words. Mark Wollner of Minneapolis Minn. is shown in testing his recently recently completed Duropower brushcutter surface drive conversion on his Hoefgen duck boat. Mark says he attained a GPS measured speed of 6.2 mph. The motor on Mark`s long tail is a box stock unmodified unit rated at 2 hp. Mark stated the motor had more than adequate power throughout the rpm range. If you zoom in you can see him smiling .
http://i259.photobucket.com/albums/hh310/JohnLOneal/P1000651.jpg

[ben2go]

ben2go, about the lake that banned 2 stroke, what lake and what technology of two strokes were banned, for some two strokes are cleaner than a four stroke
being from CA i've found even the tahoe region engine bans to be a joke at times
example:new technology two strokes only if not on a sail boat (still running a 1976 six horse johnson when i go there no complaints)

All 2 strokes are banned from SJWD lakes.No exceptions.Technology doesn't exsist in South Carolina.What's a campooter?Ya'll ever heard of such a thang?TV?Ain't that one of dem dar pictour boxes?I hate the south eastern US.

[ben2go]

Hi,

is this the type of Briggs & Stratton motor you are referring to? http://www.smallenginesuppliers.com/shop/html/pages/products/briggs_vertical_shaft_engines4299.html

I wonder how difficult it would be to mount it onto an outboard casing?

Regards.

Mark

Looks simuliar but the shaft is way different than the one in the link.My shaft is straight 1/2 inch in diameter and 1 and 1/4 inches long with a 1/4 inch keyway.I think it is specific to Murray push mowers.Also the throttle has been locked out to hold the engine at the max torque rpm.Basicly they set the rpm where they want it and bent a tab down on the throttle arm and used a stiff spring to hold it there.

[jkwhite]

New to the forum, but I have been viewing for some time... Have a question that I offer anyone to answer. Besides the obvious (handle and mount), what must be done to the shaft of a weed eater besides the placement of the prop?


John O'Neal
I want to build something like your longtail. I am also looking for the most simple thing thing I can (no gear reduction like has been mentioned). Must I follow the details that "ripped off" provided, or is there an easier way (limited on cash)

[wac m trac m]

Hello JKwhite, WELCOME!!!! I'm no pro. but I just built one pretty much just like ripped off's version. I assume in you question you mean tube that encompasses the shaft.
You got to seal it. Ripped off used grease seals but John Oneal said he used sealed radial bearings. Hey John where do you get those?

You may not have to but I think it's a good idea to weld a skeg to it as well. John could answer that better. In his earlier pics he has some of a moter with no skeg. Also a bigger prop.

[wac m trac m]

I also was hoping turn4fun...ripped off could get on here and answer this question...or maybe John could?

I was thinking of building a bigger moter with a 3 or 4 hp engine. I found a few guys that already build them. (stump jumper 4hp, utah marsh moters 7hp) I asked how fast I would go in a Otter 2000 boat. They said 8 to 10mph. Well I'm doing 8 now with my 34.5cc briggs. So is it no better to build a bigger moter? I know ripped off built some real nice looking ones cause I saw them on a different site. What is your opinion Ripped off?

[jkwhite]

Seals do make sense, that's what I was wondering. I too have an Otter (mine is the 1200). I have some plans drawn up for a mount. Since the backs are the same on the 2000 and 1200, could you take a look at them and give me a sanity check. I will try and get them uploaded this evening.

Back on the prop. I have the link to Young's. Are there any special mods for its attachment? It kinda looks rather easy.

Thanks for the info.:D

[kengrome]

I was thinking of building a bigger moter with a 3 or 4 hp engine. I found a few guys that already build them. (stump jumper 4hp, utah marsh moters 7hp) I asked how fast I would go in a Otter 2000 boat. They said 8 to 10mph. Well I'm doing 8 now with my 34.5cc briggs. So is it no better to build a bigger moter?If the hull is not designed to plane, or if it is designed to plane but it doesn't have enough HP to plane, you will not go faster with a bigger engine.

You should figure 1 HP for every 50 pounds to make a boat plane. With less than this amount of power the boat is probably going to run only at 'hull speed' and it only takes 1 HP for every 500 pounds to push a boat at hull speed.

[wac m trac m]

boat=130lbs
+ Me= 240lbs
+ gear= 150lbs
--------------
520 pounds ...wow that would be at least a 10 horse moter which would be to heavy for my little boat. The 6hp robin set ups weigh around 70lbs. I guess the weedeater route is the way to go. My moter works great now. Very reliable. Thanks again Ripped off and thanks John Oneil for all your ideas. I'm hooked and am still going to make a bigger one out of the duropower head. If I come up with anything usefull I'll post it.

[John O`Neal]

JK; If you could find a used brushcutter or possibly one from a pawn shop it may provide you with the simplest ,easiest and most cost effective conversion. All the things that you will need come on a brushcutter( controls, a boom with multiple carrier bearings, and a steel drive shaft ). The motors on brush cutters are usually larger than most weed eaters and provide more torque. A good thing. You will need to remove the gear head and make, or have made, the bushing seal combination at the prop end of the boom. The Youngs` props can generally be attached with a roll pin. Fastenal has bronze flange bearings in 5/16" id & 3/8 " id for less than $ 3 for a pack of 5. National oil seals can be obtained from almost any auto pts. store. I got mine at NAPA. Here are the numbers for the oil seals. 5/16" id .750 od National # 3140-350364 3/8" id .750 od National # 3687-330385. Starting with a brand new brushcutter unit you can figure you will probably add $50 to $75 to convert it to a mini-long tail. Mine cost $300 to build $250 was for the cost of a new brushcutter. I have posted a sketch of the bearing & seal combination I made for the prop end of my motor. It use two flange bearings and two seals. I pack it with marine grease. With the drive shaft installed it becomes a sealed unit. Good luck with your build.
Wac m : I did use a 7/8" od X 3/8" radial ball bearing on my ryobi powered unit . You can buy those bearings several places Internet vendors ,Fastenal, bearing dist. I used them only once because you have to use bearing shaft with that type of bearing. Bearing shaft is ground 1/2 to 1 1/2 thou. smaller so it will go through the radial bearing. I couldn`t find a local supplier so I had to order it on the net. The cost plus shipping just wasn`t worth it.

[wac m trac m]

Hey John is that a Youngs prop in your first pic you posted with the moter with no skeg? It looks bigger then a T10 or 12. How did it do? I noticed the newer moters all have skegs now and smaller props so I'm curious what happened?

Is the Chinese brushcutter shaft solid? stainless?

Thanks!!

[wac m trac m]

Hey JK, I used a peice of 2in angle and bolted it to the storage cover on my stealth 2000. It works ok but I want to get it a bit higher.
Check this guys idea out on the Utah Marsh moter. Looks pretty solid. I'm going to do something simular but raise it a foot. I'll post it when I'm done. I love the oarlock idea Ripped Off made. It works great and its so simple.
http://utahmarshmotors.com/plugins/albums/slideshow/slideshow.html

[John O`Neal]

Wac-m ; The prop you reference was a T-10. It worked great but I destroyed it. Investment cast alum. is brittle and doesn`t have the strength forged alum. It broke easily. I replaced it with the t-12 you see pictured in a later post and added a skeg. I broke the T-12 also but that was my fault. I now have a composite prop off of a Shakespeare Wonder troll it`s tougher than Chinese arithmetic. Young's` makes it in a alum. version, it`s the T-4.
The shaft of the Chinese (Duropower) brushcutter is a hardened steel shaft(not stainless) splined on both ends. It has a .314 od.

[wac m trac m]

I snapped my shaft today...uggghh. I was navigating some shallow water and turned the prop right into a rock at full throttle. "snap"

Back to the drawing board..lol

[Mark Wo]

Yep, that's me in the picture John posted. I'm now a famous internet celebrity (not that kind) While the motor is stock like John mentioned, the shaft and other parts required some minor work. If I can do it, anyone can do it. I followed John's advice on the bushing/grease seal unit (and other suggestions) he posted earlier. The rest was trial and error and I still have a couple of things I'm trying to fix.

Without much effort I was able to get 6.2 mph measured on the gps. I don't think more power or torque would push me any faster. With this motor I was also able to easily push through weeds without the thing bogging out.

My first attempt was to follow Ripped Off's design. I found that the Bolen's motor purchased at Lowe's wasn't up to the task. It was about 90% there but the 31cc motor didn't have enough punch to work consistently and in all conditions. It was quickly abondoned for the duropower unit found on the web. One other very nice feature of the duropower unit was it's quietness. Mucho better than the Bolens and other inexpensive chinese motors.

It was a fun project and I appreciated the information shared here by Ripped off and from exchanges between John and myself. If you are hesitant about building one of these, don't be. Easy peasey.

Mark W

[jkwhite]

Mark...thanks for that info. Are you running the 52 cc engine? My plan is to order the 52 on monday. Also, did you use the prop from Young's (the size that rippedoff recommended?

And, thanks for everyone that has answered and thrown in some info. It has really been helpful.

[alexlebrit]

I'm almost tempted to start a new post, but I thought I'd pop it in here as I have no real info to give.

Everyone's concentrating on weedeaters here, and I can see the logic, but what about other ic power tools? I've been eyeing up my old chainsaw for a while now, and combined with things I've been reading about pedal powered boats was wondering if anyone's considered a chain driven system - a bit like this (but not twisted of course).

http://www.wisil.recumbents.com/wisil/hpb/compact_hpb_drive.gif

And of course the prop would be suited to the engine's performance.

Second thing - What's the handling like on a long-tailed weed-eater boat? I imagine it'd need quite a large area to turn round, or are people using rudders?

And third - And this springs slightly from the second, has anyone used a weedeater conversion as part of an inboard drive? Then you could have a rudder although of course you lose the ability to lift the prop, but as weedeaters tend to have tiny props anyway I'm sure it'd be possible to protect it with a skeg or skegs.

[Mark Wo]

The T-10 that Ripped off used would not work on the Duropower unit due to the differencces of shaft sizes. I think John had a T-12 and I ordered one of those and I ordered a T-4. The only differences between the two is in the way they attach to the shaft. The T-4 was an easier way to attch but hte T-12 might be a better attachment method.

I don't think Duropower will be open on Labor Day.

As far as turning - it isn't like an inboard or outboard motor that is for sure. The shorter you can make you tiller, the shorter the :throw" required to turn sharper. It the pictuer John posted above, that motor had no skeg and it did not turn at all. I also had some issues with my tiller not being secure and a couple of other things but the previous motor built while it didn't run consistently it turned wll.

Mark W

[wac m trac m]

Why would you make it pedal powered? You could just paddle. The whole point of this project for most of us is the use it to get back in the marshes to duck hunt. The biggest problem is shallow water and weeds. The weed eater moter wont get you from point A to point B but it will get you most of the way there. It's way better then paddling or peddleing. The prop at the bottom of the boat would hit bottom almost everwhere I hunt/fish.

[alexlebrit]

Why would you make it pedal powered?

I wouldn't, it was to illustrate my point about using a chainsaw as engine instead of a weedeater that was all. Remove the pedals/crank etc, and put chainsaw in their place (also remove the twist in the chain cos we can just turn the saw round by 90°) You've then got an engine at the top and a prop at the bottom with a chain connecting the two. Which is vaguely like an outboard motor. The huge advantage as far as I can see with chainsaws is that they almost all have some form of clutch mechanism, usually a centrifugal clutch, so that you can start and idle the motor without the prop going round. Weren't some people having problems with the prop bogging the motor down and even stalling it?

Might not be the best for specific duckhunting conditions, but there's people looking at converting IC powertools for other purposes too.

[ben2go]

I wouldn't, it was to illustrate my point about using a chainsaw as engine instead of a weedeater that was all. Remove the pedals/crank etc, and put chainsaw in their place (also remove the twist in the chain cos we can just turn the saw round by 90°) You've then got an engine at the top and a prop at the bottom with a chain connecting the two. Which is vaguely like an outboard motor. The huge advantage as far as I can see with chainsaws is that they almost all have some form of clutch mechanism, usually a centrifugal clutch, so that you can start and idle the motor without the prop going round. Weren't some people having problems with the prop bogging the motor down and even stalling it?

Might not be the best for specific duckhunting conditions, but there's people looking at converting IC powertools for other purposes too.

Your idea could work.All chain saws made now days have a centrifugal clutch.All you would need is a chain and lower sprocket to match the saw's sprocket that gives the correct gear reduction for the prop.I wouldn't use the saws cutting chain.That would be disasterous if it broke and could sink certain boats.Not sure what gear reduction would be needed.Some chain saws have a built in gear reduction.

[alexlebrit]

No, using the saw's own chain would be a bit mad really, I have no idea what rpm my chainsaw is doing, I guess I could measure it somehow, I've bodged together a cycle computer revcounter before, so I might try it again, if I can't find it from the makers.

And yes either use the existing top sprocket or replace it with either a different (bike?) sprocket or a belt drive even?

[Mark_in WI]

I want to say thanks to everyone who posted. I think I will try one of these when I find a weedwacker to use. money is tight so i, like many, have to try this on a shoestring budget. While looking for different ways to mount my trolling motor I came across this site at duckhunting chat and I'm glad I did. I also found a guy on Youtube a guy that used his cordlessdrill, a shaft, and a prop to move his dingy. Here is the youtube page http://www.youtube.com/watch?v=NOTwJRnmrTY. It works but not quite what i am looking for. :rolleyes:
Thanks again
Mark

[Orphanedcowboy]

I am getting in a little late on the mount discussion, but here is what I did to control depth:

http://i53.photobucket.com/albums/g45/Orphanedcowboy/Hybrid%20Boat/b972f626.jpg

http://i53.photobucket.com/albums/g45/Orphanedcowboy/Hybrid%20Boat/SN850465.jpg

http://i53.photobucket.com/albums/g45/Orphanedcowboy/Hybrid%20Boat/SN850463.jpg

Also here is my mounting plate for a little would boat I am building:

http://i53.photobucket.com/albums/g45/Orphanedcowboy/Hybrid%20Boat/35a17b72.jpg


I have a lot of catching up on this thread, John, Wac M, you guys are doing some fabulous work, keep it up!

[John O`Neal]

Latest project (gear reduction Conversion) is almost finished. Two hp engine running through a 5/1 reduction max prop speed is around 1750 rpm. Any prop suggestions????

[Orphanedcowboy]

What direction clockwise or counter clockwise?

I have a clockwise rotation prop with a 3/8" diameter mounting hole, custom modified prop you can have, it was originally for a British Seagull outboard:

http://i53.photobucket.com/albums/g45/Orphanedcowboy/SN850462.jpg

http://i53.photobucket.com/albums/g45/Orphanedcowboy/SN850460.jpg

http://i53.photobucket.com/albums/g45/Orphanedcowboy/SN850458.jpg

[John O`Neal]

Cowboy ; The rotation is clockwise and my shaft is 3/8" stainless. I would certainly give it a try . I can always return it to you if it didn`t work out. Thanks for the offer.

[Orphanedcowboy]

PM me your mailing address and I'll drop it in the mail to you

[wac m trac m]

Those are some cool ideas Orphan cb. I see the office chair wheel bracket thing. Are those gun scope rings? Great job man.


John you've taken it to another level. Looks cool. I didn't think you needed gear reduction though those 50 cc moters top out at a lower rpm right?
Well you know better then me. I'm really curious how it does. Good luck.

[John O`Neal]

Wac m ; You are correct, the 52cc motors make max torque at around 5500 rpm. They produce enough torque to utilize the smaller Young`s props without a gear reducer. They work great in a direct drive format and are simple to build. The gear reduction model is just a venture to see that if by multiplying the torque available several times, through the gear reducer, that I could then utilize a much larger prop. The desired goal is to produce greatly increased thrust and some mud slinging ability.

[Orphanedcowboy]

Those are some cool ideas Orphan cb. I see the office chair wheel bracket thing. Are those gun scope rings? Great job man.


They are 1" split shaft lock collars:

http://www.allmetalssupply.com/images2/shaft_3.jpg

http://i53.photobucket.com/albums/g45/Orphanedcowboy/08e0a320.jpg

They are about $3 each at Ace Hardware. I just ground them flat on one side to make mounting them easier.

On a side note, I found 3/4" od x 3/8" id and 3/4" od x 5/16" id sintered bushings for less than $3 each and the corresponding seals for less than $4 each at Motion Industries. You can order online and they will be at your door in less than 3 days.

Motion Industries (www.motionindustries.com)

I have completely scraped my plans in favor of Turn4Fun/Ripped Off design.

There is a local company that has the aluminum tube and stainless shaft, deliverable by UPS anywhere in up to 6' lengths.

Discount Steel (www.discountsteel.com)

I bought enough material, since they were local to me, to build 6 shafts with tillers for $107, they charge a $2 per cut fee for odd size cuts, so I had them just cut everything in 12' lengths. I have one complete shaft in the books and working on a second, waiting on props.

One question, what are y'all using for a thrust washer/bearing?

I put a collared sintered bushing in the prop end of the tube, with a 1/4" thick 1" diameter teflon washer riding between the bushing and prop. I have my lock collar on the engine side to keep my shaft in the engine, but using a trolling motor prop I noticed the thrust created a potential problem.

I also created a clutch lock out using 2 1/2" aluminum bar, cut down to 2.375" x 1/2" thick with 3/8"x 24 tpi center, threaded directly onto the Ryobi crankshaft. I used 3/16" roll pins in 2 places to connect the crank with the flywheel.

I have been taking alot of pictures, so I'll post a slide show when I am done. The Turn/4Fun/Ripped Off design is the best I have seen, commercial or otherwise, very easy to follow instructions.

I also ordered some 1 1/4" and 3/4" diameter teflon rod for another experiment using his plans.




John, have you had a chance to try out the props? Also, what type of shaft does the Duro Power engines come with? Splined or square?

[John O`Neal]

Cowboy; The props arrived today. I probably won`t have a chance to test till sometime next week. The Duropower brushcutter units utilize a hardened steel shaft which is splined at both ends. The OD is .314.

[Orphanedcowboy]

How are you making the connection, welding?

[John O`Neal]

Cowboy; I assume you are referencing the prop to shaft connection on the duropower units. The Youngs props with a 5/16 id mounting hole T-4 , T-8 or T-12 will slip right on the Duropower shaft with the gearhead removed . I use a cobalt bit and a centering jig to drill the hardened shaft.

[ben2go]

Cowboy; I assume you are referencing the prop to shaft connection on the duropower units. The Youngs props with a 5/16 id mounting hole T-4 , T-8 or T-12 will slip right on the Duropower shaft with the gearhead removed . I use a cobalt bit and a centering jig to drill the hardened shaft.

Holding the prop in place with a roll pin?

[John O`Neal]

Ben2go; Yes to the roll pin method. The T-12 installs in a more conventional manner (ie) The back of the prop is slotted to slide over the roll pin which then acts only as a shear pin. The prop is then held in place by threading the shaft and installing a nut, or by drilling the shaft and using a cotter pin to hold the prop over the pin. There is a pic of that method in an earlier post.

[wac m trac m]

I like that T 12 design. I think if you hit a rock it might give a bit. The roll pin does not. Thats how I broke my shaft. I had a solid 3/8 ss shaft and it snapped at the moter end where I squared it up to only 1/4 inch to fit my briggs moter. My clutch is still in there and doing well but I found out I can buy a new one for 16 bucks if I need it.

I'm getting pretty hyped up. We are still in a drought here in central TX. I found a nasty shallow mudflat that is ate up with teal. Our early teal season opens in 2 weeks. Cant wait to use my little set up to putt in there on the shallow flat. Today I'm building a blind for my Steath. It's going to be a slaughter...cant wait.

[Orphanedcowboy]

Holding the prop in place with a roll pin?

No different than the majority of trolling motors:

http://i11.ebayimg.com/02/i/001/08/0d/c769_1.JPG

You would be surprised at how strong the roll pin method is.