12.5 hp b/s riding mower engine has no compression?
Model 289707, type 012101 Yard Machine riding mower. It was given to me in this condition. When you turn the key the engine will not turn over. The flywheel just spins. I pulled the spark plug and placed my thumb over the hole and I have no compression. I don't think it's a thrown rod. There is no crack in it, the oil level is good and no leakeage. Could a valve be stuck? If so how do I un stick it?
I just finish removing the head on my 12.5 b.s motor ..I discover that the small ring on top of the valve hole has come out and had the valve so that it couldn't close....I carefully lined it up with hole and took the end of a rubber hammer and tapped it back in ..how long it will last i have no ideal.....if anyone" has had the same problem let me how long it may run.
Sucker for bad luck
August 2012
The breather (the rectangular unit that the rubber tube from the carb runs to) you'll be able to see the valve tappets and ends of the valve stems. If the valve stems are moving when you turn the engine over by hand, it's probably not a stuck valve. If the engine is turning free, it's most likely a broken rod.
Rick
November 2006
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