I am looking at buying a boat that has a 40 hp johnson that has bad compression on cylinder 2. what could cause that, and more importantly, what would it cost to get the parts needed to fix it?
No way to know for sure until it's examined to determine cause of low compression. It could be an inexpensive head gasket, or, it could be major engine failure. Depending on year, some engine parts are difficult to obtain. Avoid it until you know for sure.
