I want to polish the ends of the cooling fins on my engine to a mirror finish, is there any product you guys know of that will protect the aluminum from oxidizing? Some kind of thermal transfer clear coat? The engine is an Evo

 

I don't know of a silver bullet for protecting bare aluminum. I would think that any type of clear coat would eventually come off or possibly discolor. I really like Blue Magic polish. It leaves a "coating," but requires periodic maintenance. The MoCo also makes a pretty nice product that used to be called Harley Preserves, or something like that. You can still get it at the dealer. These actually work, but similar to other products like Blue Magic, you have to reapply every so often. That's my dos centavos.

https://www.harley-davidson.com/stor...dividual-wipes