I have been having a pretty serious misfire and after a compression test I find that my #4 cylinder has zero compression, which I know is rings, piston, or valve issue, but before I begin tear down I wanted to perform a leak down test to see if I can determine the source of the issue, but I'm not sure how to get the #4 cylinder into TDC, anyone know how?

 

Cylinder leakage is tested with the piston at BDC, (Bottom Dead Center) when both valves are closed. Applying compressed air through the spark plug hole will force the piston to BDC, right where you need it.

 

Thanks, you're a cod fish