Lawn Mower Outboards  
By Steve Marsh -

Here is a picture of my project .Lately I have been trying to convert a lawnmower engine to an outboard. The first picture is an old clinton engine which I was given in pieces. I put it back together and it ran fine, so I built an engine mount. It's just a steel plate with a piece of pipe welded to the bottom. This fits into a transom bracket that was originally made so that you can carry a small boat on top of a station wagon. I think it said 'cosom' on the side. Then I extended the driveshaft with a primitive u-joint, and a 4.5 foot steel rod. I found a nice 3 blade prop that fit and it was time to go cruising.

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The original setup was not stable enough so I welded supports to the engine plate, along with a skeg.

The original setup was not stable enough so I welded supports to the engine plate, along with a skeg. There is a block of ash in the aft end of the support tube, to act as a bearing. This setup worked fairly well. The flywheel seems to stabilize the boat (12ft mitchell - aluminum).

The engine ran well enough but the prop fell off after about the third trip. There is no reverse with this setup and the steering takes some practice. The power was enough to move the boat along but not enough to plane. I have some more pictures of similar shade-tree engineering projects and I'll send them if you think anyone is interested.

This setup worked fairly well. The flywheel seems to stabilize the boat (12ft mitchell - aluminum).

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The second motor is based on a vertical shaft continental a-20 engine I got at a garage sale. It always starts right up, so after looking around I got a complete lower unit from a Martin outboard that spins in the right direction. The total cost for both was about $14. The drive shaft had to be cut and it fits into a tube attached to the a- 20. It is fixed in place with a cotter pin that has worn out a few times but is easy to replace.

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After looking around I got a complete lower unit from a Martin outboard that spins in the right direction. The total cost for both was about $14.

The muffler was rusted so I made a duplicate out of some scrap brass and copper pipe. The mounting plate is just a piece of aluminum (part of a stop sign) with holes drilled for mounting bolts. The engine didn't fit all the way down into the lower unit, so rather than grind away anything that may turn out to be important, I used 2 spacers made out of ash. This motor runs great and it doesn't use much gas.

SAILS

EPOXY

GEAR