Performing Compression Test
 

I've got my 2.7 engine removed from 1975 P car.

Can a compression test be carried out with the engine removed from the car?

Yes you can...but it is always recommended to do it when the engine is warm if you want an exact reading result.

It would be better if oyu could swing a leakdown, I had nominal compression, however I had a 35% leak past the rings.

What I am concerned about is a damaged valve, the engine was running fine when removed but there was a slight knocking sound.

My guess was that a compression test would easily identify if I had a damaged valve.

If you suspect a damaged valve, minimize engine rotations. I would perform a leakdown test at this point. Before testing, remove the valve covers and verify the suspected valve is not so bent it is stuck open (valve vs piston = bad).

If okay, manually rotate engine so test cylinder piston is at TDC, end of compression (careful), then do it. If you bent a valve, it'll be pretty obvious where the air leak is.

Sherwood

Ok

Thanks for the help all.