Motor has been sitting with spark plug out. I can turn crank by hand 3/4 of a turn then it locks. What can I do to break it free? Is it worth it? Dynamark mower in good shape. Sounds like it might have good rings when I turn it.
You have a rust ring - as suggested by John. You have a simple choice - you can strip the engine and clean the cylinder wall, or simply force it. This may break a piston ring, but what have you got to lose? It will probably be ok.
phil_saunders(a)bigfoot.com
Phil Saunders
April 2009
Either the cylinder has a rust ring thats causing the piston to lock up, or if its an OHV engine there may be a valve stuck open, and the piston is hitting that as it rises.
John
April 2009
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