Doing a search on mini mudmotors.....

Ed L.

Ed L.

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for my 12' boat I ran across this weedeater based motor. Thought you guys...(and gals) with foam boats or small kara sytle boats might be interested. I know the price seems high but watching several used air cooled motors going for around the same price on ebay it may not be out of line. A looked at a 2.0 hp Honda air cooled with a price tag over $1000.

http://www.smalloutboardengines.com/20hpoutboard4strokecamouflage.html

Ed L.
 
Ed,
My buddy decided not to try and market the ones we built. I will p.m. you my number, call me and I will tell you how to build one for about $165.00. Shawn


 
Here is Turn4Fun's "how to" post in the Boat Desing Archives. http://www.boatdesign.net/forum/archive/index.php/t-1681.html it is near the bottom of the thread using another name. Shawn I believe this is your buddy.

I spent many a year trying to talk someone with the tools into building these things. Finally a retired machinist in Utah at http://www.utahmarshmotors.com/Home_Page.html became curious about it. His engineering math showed that the 2.5HP honda motors would be the best bet with a specially machined prop and some minor gear reduction. He still has not completed R&D and now that Ricksaw is on the market he may not complete it. Only time will tell.

The how to post along with the photo links provided is all any handy person needs to get busy in their shop. I am thinking of a dual purpose 4 stroke weedeater. Summers on the lawn, and fall in the marsh pushing around the Duck Monitor.
 
Shawn Hollis im jelous on two accounts on cool little moter set up ther two you have a lift in your garage awsome lol
 
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Scott,

That looks like a pretty well thought out motor for the small boats. Price although a little high, probably isn't out of site for a motor that's been engineered properly. The specs on the Honda motor are pretty good. Unfortunatly for the hobbiest/do it yourselfer, $219 for the motor may be a tad high. Thanks for the response going to keep this in my possibles folder.

Ed L.
 
Shawn,

I enjoyed talking with you. Thanks for the info. I have a 31cc (? maybe 35cc) Poulan striaght shaft in the basement I picked up to try this. Think I'll take it apart and measure the components and see if they're close. If not it's off to the hardware store....;-)

Ed L.
 
Thanks Ray,

I called the guy at Utahmarshmotors and had a nice conversation with him. I really like the double u-joint/pillow block setup they use. Should be a very smooth rotating assembly. Also that it's electric start and I like the battery placement being attached to the frame rather than seperatly placed in the boat somewhere. This one's in my possibles folder also.

Ed L.
 
Guys,
I had a lot of interest in the mini motor I posted. I did follow Turn4funs example a lot. I will take a few more pictures tonite and try and do a little tutorial for those that want to try and make one. I'll put it on this thread. Shawn
 
Guys,
I had a lot of interest in the mini motor I posted. I did follow Turn4funs example a lot. I will take a few more pictures tonite and try and do a little tutorial for those that want to try and make one. I'll put it on this thread. Shawn
Click to expand...

Thanks! I have already been to the hardware store checking out weed eaters.
 
had a buddy make one as well, his however, never worked up to expectations due to gear reduction being off. Once you dropped the motor into the water more than 1/2 way, the torque just stopped the motor dead....I always knew there would be a way, just never took the time to figure it out.

shawn, I can't wait to see what you have. Thanks for taking the time.
 
Alright guys I will do the best I can to explain the process I used to build my little mud motor. Go to Lowes and buy a Bolens curved shaft weedeater 31 cc ($69). While you are there pick up a universal throttle cable ($6). You need the drive portion at the weedeater head to use in your motor. Bolens uses a piece of aluminum that is crimped in the end and bushed to 5/16.

You need the shaft that rides in these bushings (sorry I do not have a pic of it). A snap ring keeps it from sliding out the end. Go to your steel supply house a get some thin guage 1" tubing. Have a machinist make make you a new shaft for the drive to ride in, some where around 2" long 7/8" o.d. with a 1/2"center hole. Bush it to 5/16" and check the fit of your little drive shaft. Weld a skeg to the prop end and next you will install the worm drive.

This is the casing out of an Echo strait shaft weedeater. The one out of the Bolens would not fit because the i.d. of the tubing I used was to small. Cut your tubing so that there is the same amount of worm drive sticking out to engage in the motor. Mount the motor on the new tubing and make a way to mount it. Here is what I did, it is an oarlock that I clamped around a tube I made out of delrin.

You can also see how I mounted the handle I made out of 1" conduit. You could probably use the curved shaft from the original weedeater but I had made this handle for another prototype so I used it. I mounted it with a piece I robbed off of an Echo weedeater but you could just weld it if you wanted. The prop comes from Youngs Propellors in Missouri (Google them). The out side of your drive has a 3/8" o.d. so get a couterclockwise rotating prop that will fit a 3/8" shaft (19.95)

This is youngs model T-10.
I hope it is clear as mud now, it makes sense to me but I may not be the best teacher in the world. Shawn
 
Shawn -

Thank you so much for posting this informatio. As with anytihng along theses lines, more questions arise and I hope I don't overwhelm you with them

Is this the Bolens trimmer you refer to? Why the curved shaft trimmer verses the straight shaft trimmer?

http://www.lowes.com/lowes/lkn?action=productDetail&productId=183780-65481-BL100&lpage=none

Is "ripped off a friend" of yours (or is it you) and are these plans similar to yours? It seems that "ripped off" and turn4fun are one in the same people - right?

http://www.boatdesign.net/forums/showthread.php?t=1681&page=6

found and interesting video of ripped off's unit in action.

Finally, do you think this is a doable project for a novice in stuff like this? It sounds like a fun and inexpensive winter project (inexpensive in as if I screw it up, I don't have much into it.

Thasnk Shawn, I really appreciate the information.

Mark W

http://www.boatdesign.net/forums/showthread.php?t=4136&page=2
 
Shawn-

How well does it run? Do you take it through really thick stuff? Did you play around with the gear ratios any and install a gear box? I thought that a regular weedeater motor with no gear changing was too fast, but how does your rig work? That's a pretty sweet set up you've got there, and I think I'm going to give it a try. There are some places that I'd love to take my little layout boat, but the hydrilla is totally topped out so if it pushes through topped out stuff, then I'll probably go ahead and give it a try. Thanks for posting this.

Dani
 
Thanks Shawn...This helps alot.

I had also been thinking of a little more traditional looking mudmotor. Here's a kart/pocket rocket electric start 49cc engine.

http://www.monsterscooterparts.com/49encowielst.html

These motors are available of ebay with some substantialy less expensive.

Of course a more traditional frame/shaft and seperate fuel tank and battery is required. Looking at the scooter batteries these things are supper small. I'm looking at these batteries also for running light options. I had been doing a little layout work with the Rickshaw gear reduction in mind as well as the Scavanger design and was thinking a 2:1 belt pulley system might work with 49cc engine which comes with a kart type clutch. This motor reportedly pushes a 250lb occupant in Tanaka paveracer to 25mph. Keep in mind this is a go-kart with a larger drive sprocket than you could use on a mini mud motor.


Here's a bill of material list that that fellow named Ripped off used on the boatdesign.net site.


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
 
All,
It pushes me a dozen or dekes, gun and other paraphenalia as well as any 30lb. thrust trolling motor would. And it is a lot less aggravating.
Dani,
You can not run it full throttle only about 1/2 throttle, if you give it to much gas it will choke down. I think gear reduction would be a great idea, I may play around with a backpack blower (58 cc) before next season. If I geared it 2:1 I could use a larger prop and get more thrust. As it sits right now I do not think it would handle Hydrilla very well.
I do not Know Turn4fun except from forums, he is a callmaker also. Good luck Shawn.
 
Ed,
Are those trannies for the scooters geared? Or is that really just a housing for a clutch? I wonder if a clutch would hold up? See now you are going to make me start working on something new right here in the middle of our season HA HA. Shawn
 
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