[hurryinhoosier62]

Originally Posted by Schurkey

Leakdown testing with oil? I'd expect the air pressure to blow the oil past the rings in short order, leaving no difference with or without oil added to the cylinders.

You use the oil to seal the rings AFTER you have established a base line reading. IF the pressure goes UP, the rings aren't sealing correctly. If it stays the same or DECREASES, start looking for leaking valves(especially exhaust valves). We've been doing this for DECADES on recip aircraft engines. I know many here will not agree, but cylinder glazing is the prime reason why I DO NOT use engine oil on the pistons and rings when assembling an engine.