Weed eater engine conversion

[Lockdup]

Hey Guys,
I have been reading this forum for awhile now but never posted. WOW, some great designs out there. I have been folowing Orphaned Cowboy and Ripped off's posts and trying to figure out some things.
1. How do I lock up the clutch. I have the Ryobi BC30 like O-cowboy suggested.
2. I can't seem to figure out what prop to try. It seem as if everytime I try to get one, someone posts saying it won't work.
Orpaned Cowboy, Where did you get that 4-bladed Prop and how well does it push your boat.
I will be hunting out of a Final Attack this year and would like to have all my ducks in a row.
Please advise.

Thanks.

[wac m trac m]

Man that is toooo easy. LOL
Everytime I see these ideas I feel like such a D...A..!!

How does that oar lock hold up to the vibration?

[Orphanedcowboy]

I like the oar lock idea, I had considered it after reading about others using it. I just wanted something a little stouter and rigid, with a way to control depth. I originally built the first version with out the depth control cross block, but after 2 trips with out it, I added one and it makes a world of difference.

For my next motor I will be using Ripped Off's design

My lock out is really simple, but requires either a high speed drill with a 3/8" chuck, a drill press or a lathe. The Ryobi uses a 3/8" x 24 tpi right hand tread clutch. I simply got a 2 1/2" piece of bar stock drilled a pilot hole as close to center as possible, you can cheat to find center, I double back taped the block to my 3" sander backing pad and used a piece of sand paper to find center. I drilled out the center in steps until I was at a Letter Q drill, then I treaded it with my 3/8" 24 tap and used the tap as my mandrel. Chuck the tap up in my drill press and "turned" it down to 2 3/8" using a piece of sandpaper double back taped on a small wood block, 120 or 80 grit will work just fine. It may take several sheets, but you will get there. Most importantly don't rush, the slower you go the more true it will be. I plan on using my lathe on the next 2 I build, I made me a mandrel for my lathe, so now I am good to go. I checked the run out on my hand built version and it was with in .025". Next drill two 1/8" diameter holes opposite of each other in the very center of the new "clutch" and install two 1/8" roll pins with 1/2" still protruding. Lay the new "clutch" on top of the clutch housing, make sure the new "clutch" is centered and mark on either side of the roll pins. Cut from the center with of the mark with a dremel until you have a slot just wide enough for the pin, go to the other side and do the same. Install the new "clutch" and make sure the roll pins touch the driven side of the clutch housing.
Here are some pictures of my lock out:

[Orphanedcowboy]

I have 2 lower shaft's with gear heads and threaded mounts that are 3/8" diameter. One is new, the other used on my first version motor. I will send the correct prop, a Young's T-8, with each one. The used one has been modified for the Ryobi engines. If you need one just pay shipping and I'll send them out to you. Both are off of Ryobi 31 cc motors and have the 1/4" squared drive shaft.

John I found another prop that might work, but don't have a clue as where to buy it:



It too is a British seagull prop

I was also at Home Depot this morning looking at donor units, and one caught my eye. Ryobi now makes an electric start weed eater, it uses their 12 volt rechargeable battery that their power tools use. The starter motor is mounted to the rear of the engine, and doesn't interfere with the shaft location. It uses the same front cover assembly as the Ryobi's I have been using. I think I am about to get lazy and buy one for my next version. I won't be using the supplied battery, since the duck boat I am building will have a deep cycle battery for lights. #26 is the starter. The electric start version is $10 more than than the brush cutter version I used for mine.

[Mark Wo]

Originally Posted by wac m trac m

Man that is toooo easy. LOL
Everytime I see these ideas I feel like such a D...A..!!

How does that oar lock hold up to the vibration?

There is no more vibration with this method than any other as far as I can tell. Get a good motor, like the duropower and the vibration and noise is greatly diminished.

With the straight shaft type of mud motor, depth control is done by pivoting the motor up and down in the mount itself. You want less depth, you push down on the tiller, you want it to go deeper, you lift up in the tiller or if you have it weighted properly the motor will naturally go deeper when you let go of the tiller. By the way, I highly recommend you weight your motor so that when the motor is not being used, the prop goes in the water, not out of the water. Much much safer way to go in my opinion.

Also, the duropower clutch is a much heavier duty clutch than what comes with the less expensive Ryobi and Bolens 31cc motors (or others) that you can buy for less than $100 at any of the big box retailers. I have used the duropower clutch for about 5 hours now with no issues. The clutch is a VERY nice feature to have and I would not build another one of these types of motors without one. Having the ability to start the motor without the prop spinning is a big bonus. Being able to leave the motor running without the prop spinning is another big bonus.

Finally, I had troubles with the smaller motors as did John O. I couldn't get it to work consistently which being a hard core duck hunter I need it to do. I don't want to be a mile or more downstream from my truck at below zero temps and not have the motor work flawlessly. I have no doubt the duropower unit will not let me down. I did not feel that way with the cheaper motors. I know that Ripped off had good luck with the 31cc motors as did others but I could not get it to work - it did not have enough torque to always spin the prop and the motor was always bogging down then dying.

With the Bolens or Ryobi you can easily count on spending $150 to get the shaft, driveshaft tube, bushings, throttel cable, tiller mount, throttle, motor and more. Then depending upon your access to a shop,, you can spend more money machining the motor end of the driveshaft to fit into the outdrive of the motor. For less than $100 more you get a much nicer unit almost ready to go out of the box with the duropower and you can find parts if it ever breaks. And nope, I don't work for or with these guys, they have just got a great motor and price.

Once again, just my opinion.

Good luck. 2.5 weeks until northern zone opener.

Mark

[ctc982]

Hey guys, I am new to posting here so I hope that this turns out ok. Right now I am here in Texas riding out the remainder of Ike who decided to come in and kick our chances at opening weekend of early teal season in the ****.
I have been following these posts for a long time and as a matter of fact spoke with Mark on the Motorbike forum.

I have a Otter Stealth 2000. I first got this idea when I saw the Crawdad mud motors and started chasing the rabbit. Since then I have followed this and have ordered the 52 cc Duropower. I expect it to be delivered next week and I and going to get a money order to Young's on Monday. I plan to get the T12, I like that attachment method. What do yall think?

John O'Neil - I saw you bought some after-market performance parts for your Duro...where could a fellow find those, because Lord knows we always need more power. I will probably also be in touch with Mark as well as yourself since you have the same rig.

Thanks guys, I will contribute in any ways and ideas that I have.... if you guys have left anything out..lol

Have a good weekend.

CTC

[wac m trac m]

Welcome CTC, I'm sure John or Mike will help you out soon but I do know John wrote that he bought the parts for his moter right off the duropower websight. I think the air filter is a k&n. He wrote about it a ways back.
What part of TX are you in? I'm in Wimberley, if your nearby I have some good friends who weld aluminum.

[John O`Neal]

Welcome to the forum CTC; I purchased the performance parts from a couple of different Internet vendors . I will look up their websites and outline the modification procedure. The modifications are, as Mark W. says "easy peasy". I will post up that info. soon. Which type of conversion are you going to build, outboard style using the gear head, or a direct drive mini-long tail ?

[ctc982]

Wac,

I am near Texarkana, I just got my power back on. Ike knocked it out for about 30 hours.

John,

I am going to make the long tail version. We hunt alot in flats and stumpy areas.
Are these shafts aluminum or stainless?

Has anyone ever tried to shorten the tails to 4 feet or so? I see the benefit of having it longer because the longer it is the better of an angle that the prop is in. However, it will make turning like turning an 18-wheeler, right? The shorter the shaft the smaller turns that can be made, right?

[John O`Neal]

CTC; First off, the drive shaft of the Duropower is hardened steel 5/16 dia. (actually .314) the carrier tube (aka boom) is .058 wall X 1.020 od alum tube.
Engine Modifications---- Rocket key; an offset wood ruff key that replaces the stock key. It advances the timing 10 degrees. It definitely picks up the throttle response. I purchased mine at ScooterParts4Less.com cost $6. You will need the large size key for the Duropower eng. On the website there is a tutorial on the installation procedure. Note!!! The Duro eng. rotates counterclockwise so the offset in the key must go towards the direction of rotation or you will retard the ignition timing.
Replacing the stock air filter system. I do this for two reasons . It is a relatively inexpensive way to pick up power and it provides a method for instant starting on those cold duck chasing mornings. I always carry a can of starting fluid in my layout boat. Instead of pulling the cord on a cold eng. multiple times I give it a small spray directly on the filter element ,choke and pull. It will start on the first pull 9 out of 10 times. The air filter and velocity stack with built-in choke plate come from the same supplier. WWW.davesmotors.com The air filter # af22x (pic a color) $12 The velocity stack with choke. # af315. cost $14 You must have the velocity stack in order to mount the air filter.
Raising the compression. cost 0 dollars. result improves overall power increases torque. Remove the cylinder from the eng. /remove the stock cylinder gasket/ make certain that the crankcase and the cylinder mating surfaces are clean/ apply a THIN !! coat of high temp silicone sealer to the mating surfaces carefully reassemble. Note ! prior to reassembly loosen the ignition coil bolts we will need to reset the air gap between the flywheel and the ignition coil. (easy no big deal) Preparing to reinstall the cylinder over the piston/rings. It is always a good idea to check the position of the rings before attempting to slide the cylinder over them . The rings are pinned to prevent rotation. Make certain the rings are not overlapping the pins in the ring groves. After reinstalling the cylinder we will reset the air gap between the magnets in the flywheel and the ignition coil. The recommended clearance is .010. Take a standard business card place it over the magnets in the flywheel , rotate it around until it is under the ignition coil. The magnets in the flywheel will pull the ignition coil down sandwiching the business card . Tighten the ign-coil bolts and remove the card . The air gap is set.
The muffler modification to relieve some of the back pressure in the muffler is presented in an earlier post in this thread . It lets the engine breathe easier. Well that's what I did to my engines they start and run fine, and are noticeably more responsive than a stock one.
You are going to need some type of a bearing and seal at the prop end of the carrier tube. I included a pic of the one I made for mine. I also included a pic of the prop installation of a T-12. Good luck on your build. If you have questions don`t hesitate to ask.

[wac m trac m]

OK now I hate my briggs engine LOL. I didn't know about duro power yet when I bought it.
Hey John, how did the gear reduction do? Did you try it yet?

What is the thing in the 2nd picture above the prop? Is that how the shaft mounts to the moter? Does it come with the moter?

[John O`Neal]

Wac m : The piece you are referencing is the front cover of the 5/1 reducer transmission. I had just mocked it up prior to welding. You are correct it allows me to mate the carrier tube to the trans/motor assembly.
I am going to test the gear reduction motor in the A.M.. Actually we are going to do go teal hunting and test the motors also. The following pic is of the gear reduction motor finished with the exception of the addition of a skeg. I won`t put one on till I arrive at the correct prop size for the unit.

[Orphanedcowboy]

John, anxious to hear how the hunting and the testing went.

I just realized, the drive shaft is not splined the entire length on the Duropower units. The Shindawia and Tanaka motors I have all have splines the entire length of the shaft.

Please hurry and post up the results!!!

[wac m trac m]

Man that is one awesome prop. I'm excited for you.

[dan-n-kim]

I've been reading alot of this and you guys got it going!!!! I've made my own; Toro clockwise with a t-8. Can't get the motor to wind out??? Half throttle is all I get and the clutch is getting warm (hense the half throttle). Any suggestions??