How to engage the PTO?

[bertsmobile1]

Actual compression numbers are meaningless as there is an automatic decompression at cranking speeds and the amount of decompression will vary with valve lash & rotation speed.
However the difference between the 2 says that either the lash on the left is too big or the left has a blown gasket.
They are a good motor so worth the effort of rebuilding but before you go spending lots of money check the big ends for play.
Poke something down he plug hole that can stay in contact with the piston for the entire stroke.
Push against this stick while rotating the engine. At TDC & BDC there should be a smooth change from up to down & visa versa.
If it clicks at TDC or goes hollow at BDC then the rod is cactus and the motor is going to be an expensive repair.

 

[Dowd_Elwood_P]

Thanks, Bertsmobile1! I'll give that test a try & report back.

 

[Dowd_Elwood_P]

I didn't try the test. The spark plug hole doesn't look like it would line up with the piston. Looks like I'd have to take the "head" off to have a straight shot at the piston. Thought I'd double check before I stuck something in the cylinder.