I bought a broken 5 hp air cooled Yamaha 2-stroke outboard engine. So spark and such. (it helps if you’ve got a clip for an deadmans switch) Anyways, got it to run nicely. However, the cilinder head has cooling fins on it. And 2 of them were broken/still on there. But when I tryed to bend them back in their stock position, I suddenly had 2 pieces of aluminium in my hands.
Considering I’m going to use this engine for an project, where it goes into a space with little airflow, I want to have all the cooling capacity. This engine is probably at least 35 years old. I can’t weld aluminium, and even if I could, I wouldn’t attempt it. Very brittle and such.
I can try to drill the pieces, and attempt to bolt them back on. I’m however not too sure on how effective this would be, and how well it would connect.
Second option is using epoxy intended for metal. Looking at “Pattex Power Epoxy Super Mix Metal”. A brand called “Bison” has a scimilar product. However, the Pattex version goes up to 150 degrees C, while Bison only goes to 100 degrees C.
How hot does an aircooled engine (preferably like mine, which is 2-stroke and revs up to about 5500 rpm) get? Would this epoxy stuffs be a good idea? Or should I just try to find the money to get a replacement cilinder head. (the engine runs just fine, vid can be found here: https://www.youtube.com/watch?v=n6R7JyCbANw )