I am working on one of these now.
Compression 60 psi.
I have recently bought a leak down tester and have used it a few times. I am in the process of learning to trust my piece of test equipment.
An example: On the engine above, what I call a lot of air was coming out of the oil breather.
So I it needs rings.
I made an adapter and I connect it up to a tyre pressure pump, it gives me enough air to do the testing.
I have sealed quite a few now with RTV silicone and they dont leak oil and the end play on the crank is ok as the silicone has some thickness to it, not sure what others do. I have cut them out before using a ball pien hammer and a manilla folder.
If you suspect valves as Pitrack 1 has said, prior to opening it up, try another head if you have one.
Always tough when you are trying to keep the job economical, but trying to maintain good standards and not have to scrap the engine.
