Weed eater engine conversion

[muddin redneck]

kengrome,
here is the site that i was able to find them on http://www.mcmaster.com/#sleeve-bearings/=58xqpy on this page it tells you about the different plastics that are used in them and the applications they can be used for some are for under water applications which i think would be ideal in this situation. i am in the process of building a 24hp godevil type motor progress is slow but hoping to post some pics soon. after this motor is done i am going to make one with a 13hp clone with electric start from harbor freight. i am going to use a straight shaft design with no u joint on this on and im planning to use the PTFE type bushings listed on the website i posted above. hope this helps.

[kengrome]

Thanks muddin redneck for the reference, I'm going to look into those sleeves!

[John O`Neal]

The bearings used on the Thai longtails I purchased are definitely plastic . This is not a new technology as the Hawaiian Green Corp. utilized this type of bearing in their lightweight Cruise-N-Carry outboards over 20 yrs ago. Below is an excerpt from the McMaster Carr catalog showing the plastic sleeve bearing material they offer.

Nylon— A fairly slippery bearing surface that handles light duty applications without lubrication. Rigid and abrasion resistant.
MDS-Filled Nylon— Offers the same qualities as nylon combined with wear-resistant molybdenum disulfide (MDS), which makes it self lubricating.
UHMW— Ultra-high molecular weight (UHMW) polyethylene is USDA approved and FDA compliant. Ideal for wet and corrosive environments.
Delrin— Economical alternative to PTFE. Strong and chemical resistant, with low moisture absorption.
PTFE— Has the lowest coefficient of friction of all our bearing materials, so it's ultra-slippery. Offers excellent chemical resistance and performs well at extreme temperatures. Bearing Material Temperature
Range Pmax Vmax PV
max

[Bob Eames]

What is the name of the plastic? Can you post a link to it?
__________________


The plasic they are refering to is probably white teflon. You can find it online in alot of places very reasonable.

Bob

[GOOSE316]

Goose, you need a honda clutch kit..that is what houses the square shaft...also the kit i bought was more like 7/32nds instead of a 1/4/

[pistnbroke]

photograph ? part number ? from a honda what ? I dont think the one from a CRV will be appropriate do you ???

[muddin redneck]

i got a question for all the experts out there. i am building a go devil type mud motor and i am wondering what to put in the shaft tube for lubrication lower unit oil for outboards or marine grease? the store bought go devil uses grease and a pressurized lubricator with a grease zert on it. my first thought was to use grease because i think it would help keep out any water because it is thicker and would be harder for water to seep into it. any input would be greatly appreciated.

[GOOSE316]

I don't remember part numbers...

[muddin redneck]

How critical is it to have a cavitaion plate on a mud motor i'm building one and i am thinking of leaving it off with the cause a problem with how well the motor will run?
Thanks

[wac m trac m]

Thats covered on here way back when ripped off was posting. He said it was not necessary. He even thought they run better without one. I put one on my moter and think it helped keep the moter right at the surface of the water where I wanted it and it would help in grass if you had more power..mine was a 32cc

[muddin redneck]

thanks for the info wac m. my engine is gonna be a bit bigger than a 32cc its a 24hp(670cc) honda. i got an email from Mark Cheney and he says a cavitation plate if made properly is great b/c if holds the prop out of the water like a wing on a plane and it pushes prop wash water back down on the prop and makes more thrust so i'm gonna put one on mine.

[wac m trac m]

Cool cant wait to see it..I bet I'm to late but on the oil or grease issue. I would say grease. Oil will seap out easy and you'll always be maintaining it then. Even if water gets in the grease will do it's job.

[pistnbroke]

If the lower end of your shaft is sealed with an oil seal then oil is the best ...ATF is excellent ...remember real ships mix oil and water for shaft lubrication ....If you have plain bearing then grease with a grease nipple is the way to go ...

[WesS]

Make sure you have a straight shaft weedeater. Attach a small prop to it (must be small because of revolutions). Make a 360 degree holding bracket to hold on to transom. Thats about it. Most of these conversions have been for a mud motor for duck hunting. Good luck.

[muddin redneck]

the tube will have a tapered roller bearing with 2 oil seals in the prop end, there is 2 brass bushings in the middle of the tube, and the engine eng of the tube has one oil seal in it and lastly the shaft runs through a cast flange with hi speed greasable bearing in it. i did put a grease zert on the prop end where the roller bearing is and im gonna keep grease in it then fill the rest of the tube with 90-140 gear oil.