string trimmer/mud motor

gregbires

Member
Some time back I saw a picture posted that looked like someone took the motor and shaft of a string trimmer and fixed it with a prop similar to a mud motor. I thought this would be great for a canoe. Does anyone know how this was done? Greg MLB
 
Greg,

I think I remember at least two guys doing it. Mark W. from Minneapolis/St. Paul and Ed L. now from Florida. Try looking up their old posts from a couple years ago and you might find some info.
 
Can probably google it and come up with some hits.
High revs & no torque seem to be a problem. hard to get a prop to bite at those RPMs.
Some guys came up with gear reduction, some with a prop with a shroud around it.
Overall, seems like a lot of work.
 
That would be me. I've built 3 of them and each one gets better and better. I also have a Rickshaw unit that utilizes the small honda mini 4 stroke. Send me your email and I'll send you a document that we have put together documenting how these have been built. Here is a link with more information than you care to read believe me. Also, anyone who tells you these won't work (and there will be many of them) has never built an actual unit. They work and they work well. They have propelled my boat (Hoefgen duck boat) 6.2 mph upstream.

http://www.boatdesign.net/forums/diy-marinizing/weed-eater-engine-conversion-1681.html

Mark W
 
Mark,
Sounds like y'all have it figured out. Good job.
My comments were based on the 1st couple of guys on here who tried it and didnt work well.
 
Hey Carl -

No offense taken Carl. It I had $5.00 for every person who said it wouldn't work, I'd have made Eric P's annual salary by now. Even when people see it running they don't believe it is built around a weed eater motor.

Also, I still haven't gotten the one motor running. To be honest, I never took the time to do so as I have two others that are running well. Maybe some day.

Here's a pic of the 52 cc motor pushing the boat over 6 mph at the LaCrosse gathering a couple years back.

[inline mm1.jpg]

Mark W

View attachment mm1.JPG
 
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