Re: Low compression 1984 Mercury
Checking is not difficult. with engine warm, spark plugs out, throttle open. pull starter 3 or 4 times tilll gauge stops rising, or use electric starter. If cylinders are not within 15lbs of each other there is a problem. Could be as simple as sticky rings(usually easy to fix using a combustion chamber cleaner) up to and including broken rings, scored cylinders/pistons(require complete teardown of power head)
