Build story
I decided to make this outbound as I had a push mower lying around with a broken blade coupling that was unavailable to buy. After long time deciding what to do with it, me and my friend decided to make it into an outboard and make a homemade plywood boat to put it on. For some cheap fun
To start with I stripped the engine off the mower and scrapped the rest.
I then had to source a gearbox, propeller, drive shaft and suitable coupling mechanism which ended up being the most difficult part. However all were sourced fairly cheap on AliExpress after much searching. Altogether the parts for this project cost roughly 70 euro.
While I waited for all of that to be delivered I welded up the frame for the engine and made the pivot point out of a trailer door hinge. I also mounted the engine on large rubber vibration dampers which turned out to be invaluable as she vibrates a lot when running.
Once all my components arrived I roughly welded up the midsection out of some scrap around the drive shaft. The drive shaft is made from some m10 threaded bar I had lying around and a spline shaft I bought for the gearbox I was luckily able to find a suitable coupler online to join the 2.
When I eventually fired it up it worked great although it vibrates a lot, probably from poor alignment between the engine and gearbox but its not that bad for a 70 euro outboard. I now brought it out onto the lake 4 times this year and it's be going well although it can sometimes get a little hot if I run it for too long without a rest.
It's a lot of fun to use and is a lot lighter then a normal outboard. It's also air-cooled which makes it so much simpler than a normal outboard. However one of the drawbacks is that its constant speed with no reverse so as soon as you start the engine the propeller won't stop until you shut off the engine. As it's just hard linked to a fixed 90 degree outboard gearbox. But that's fine I normally just paddle in the last bit
To start with I stripped the engine off the mower and scrapped the rest.
I then had to source a gearbox, propeller, drive shaft and suitable coupling mechanism which ended up being the most difficult part. However all were sourced fairly cheap on AliExpress after much searching. Altogether the parts for this project cost roughly 70 euro.
While I waited for all of that to be delivered I welded up the frame for the engine and made the pivot point out of a trailer door hinge. I also mounted the engine on large rubber vibration dampers which turned out to be invaluable as she vibrates a lot when running.
Once all my components arrived I roughly welded up the midsection out of some scrap around the drive shaft. The drive shaft is made from some m10 threaded bar I had lying around and a spline shaft I bought for the gearbox I was luckily able to find a suitable coupler online to join the 2.
When I eventually fired it up it worked great although it vibrates a lot, probably from poor alignment between the engine and gearbox but its not that bad for a 70 euro outboard. I now brought it out onto the lake 4 times this year and it's be going well although it can sometimes get a little hot if I run it for too long without a rest.
It's a lot of fun to use and is a lot lighter then a normal outboard. It's also air-cooled which makes it so much simpler than a normal outboard. However one of the drawbacks is that its constant speed with no reverse so as soon as you start the engine the propeller won't stop until you shut off the engine. As it's just hard linked to a fixed 90 degree outboard gearbox. But that's fine I normally just paddle in the last bit