John Deere STX38 with low compression, 65psi (lawn tractor)

Before I rip this thing a part dose anybody have any thoughts on a problem other than rings? It's just lost power over time. Or that's what I was told....
Thanks for any help.
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Sounds like you might want check the gap on the Intake & Exhust valves first. Just my first thought.
Good Luck, Jeff
Kevin wrote:

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Also, check for carbon buildup at the valve seats. Not likely but an easy check.
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Thanks Jeff
I got the manual on line last night, should have done that before I posted the question. turns out normal range is between 80 and 50psi. Maybe the rings and valves are Ok. The air filter was a mess, looks as if it hadn't been changed or looked at for a long time. It was covered with moths, leaves and other muck. Maybe it wasn't getting enough air? Maybe I'll rebuild the carb, if it's anything like the filters it'll need it.
Kevin
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Score the cylinder walls.
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if its a kohler command engine, and it has any oil in it other than 10w30, it will cause a loss of power by not letting the valves close consistently.lucas
http://www.minibite.com/america/malone.htm
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