I am doing a leak test on a M54 motor I got in SoCal before installing it. I am getting readings that are lower than what I expected; holding between 65% to 80% pressure at 100psi. I can hear air hissing slightly and can feel it coming out the exhaust at TDC.
My question is because this engine hasn’t had oil in the heads, should I expect the valves to not seat as well? Should I squirt some oil into the valve guides and try again? Or something else given the circumstances.
Also ran an inspection camera into the cylinders. The pistons look like the have a light sandpaper covering of carbon. There was oil leaking down into the spark plug tubes. I intend to change the cover and oil housing gaskets before installing.
Thank you in advance for your inputs,
Bob
Angie's don't need any oil to do a compression test either the valves are ceiling or not yours aren't ceiling they need work
Scotty,
Thanks for the feedback. Unfortunately I didn’t vet this salvage yard out sufficiently. I was recommended them by another yard. When I looked on Yelp, they have the same pattern of selling worn out engines but claiming they are low mileage,<100,000 miles.
I thought buying a salvaged motor would be lower risk than rebuilding an engine that was run hot. Guess I was wrong. Maybe if I get the head redone, it will be a descent engine.
Thanks again,
Bob