Low compression

Good afternoon.

To determine the failure, you need to remove the spark plugs and get an adapter to screw into the head where the spark plug goes. Then you inject shop air into the cylinder. Then you look for the air leak. It will show in either:

1. The carburetor, this means intake valve.

2. Exhaust pipe, this means exhaust valve.

3. Radiator, this means a head gasket.

4. Oil fill cap, that means either a piston or piston rings.

Roy

Squirt a little motor oil into each cylinder before you repeat each test and if the psi goes up you have worn piston rings on all of them.

Yes, you do it for each cylinder.

Have you checked for spark and fuel?

Roy