Re: Merc 800 EL Stuck Engine

[David Stanton]

First, determine if the powerhead is stuck, or is it the lower gears rusted up? or I have also had water pump impellers with broken vanes stick the motor. If you can wiggle the flywheel back and forth at all, (often when a motor is totally stuck trying to turn it over with rope or electric, you can still wiggle the flywheel back and forth a tiny bit with your hands or with a wrench on the flywheel nut), stick a long screwdriver in the spark plug holes while you wiggle the flywheel back and forth and you can feel if the piston is moving slightly with it. This method has helped me determine which piston or pistons are stuck on several motors. The Kroil you are using is good stuff – if you can, position the motor with cylinder heads up so the kroil runs down on the rings and stays there.
Good Luck!
Dave