I mean that whatever the problem is, you are going to need to take the head off to accurately identify and then correct it.

Might be the rings gone, could be a big score on the bore, could be exhaust valve not sealing well, could be inlet valve not sealing well etc

either way, it needs its head off!


before you yank if off though, if you have a compressor then pump some air into cylinder 1 and have a listen to where its coming from, can be useful.

if you hear it at the dip stick its the rings/pistons/bores, if you hear it at the inlet its the inlet valve, if you hear it at the exhaust its the exhaust valve, but in all cases, you still need the head off to fix it.