Homemade Lawn Mower Outboard Boat Motor




this was my first attempt at this idea. i was looking to get a motor for my little gheenoe and i could not afford to buy a new motor for it so i looked around my town while driving around and i found a 6hp lawn mower that was not running, and a friend of mine had a not running 9.9hp Johnson outboard. so i got both items for free. then it just took a little planning and some faith.

1st step.
remove both motor from there devices.

2nd step.
lawn mower motor measure the shaft on the outboard motor and then drill the shaft on the mower to the same size

3rd step.
drill a set screw in the mower shaft

4th step
build a adapter bracket form the hollow leg of the outboard motor so it can be mounted to the lawn mower motor

5th step.
bolt it all together and then test it out

6th step.
Paint the unit.

7th step.
mount to boat and use it.


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2 Discussions


2 years ago

"Im thinking about doing the same thing, I have the same outboard lower unit but im wanting to use a new Brigs 19hp in mine and im going to make it where I still have forward neutral and reverse. How did you make your coupler to connect the engine to the drive shaft? Can you email me plans on the coupler?


3 years ago

Love the concept oceansidegrp! I'd so do this if I was in your situation.

Would you be able to split all those steps into separate actual steps and use photos and descriptions to explain each part? For example, how did you build the adapter bracket to mount the engine? What did you make it from? What tools did you use?

This is right in the spirit of Instructables, but I'm not sure if some of us have enough of your skills (apart from Reallyme, of course!) :)