Kohler no, Briggs single OHV yes.Diagnosis - broken compression relief valve and damaged camshaft. Replaced camshaft. Evidently not a very common issue.
If no fluid is in the cylinder, it's not hydrolock. You need to first adjust the valves, then start troubleshooting other things.I have a Lawnboy 10730, with a Kohler XT650 engine. Five years old. Seems to have developed hydro-lock, whereby I can't pull the starting cord. I remove the spark plug, and I can pull the cord fine fine (though nothing comes out of the plug hole - I would have expected some oil to shoot out). I replace the spark plug, and I can't pull the cord again. What's the fix???
Might also be something wrong with the pull cord , I know sounds crazy.I have a Lawnboy 10730, with a Kohler XT650 engine. Five years old. Seems to have developed hydro-lock, whereby I can't pull the starting cord. I remove the spark plug, and I can pull the cord fine fine (though nothing comes out of the plug hole - I would have expected some oil to shoot out). I replace the spark plug, and I can't pull the cord again. What's the fix???
I think I will install a valve for shutoff.Especially since my mower is now doing exact same thing a season and a half later afterCharlie, I once had hydro lock on my Troy-Bilt tractor from gasoline. I could not get the seat for the needle valve out to replace it so just installed a valve between the gas tank and carb. Have not had a problem since and the engine does not seem to use more gasoline than it did before.
The Kohler website pictures of the XT650 appear to show a fuel hose from the tank to the carb. There might be a way to install a valve in it to verify that it is not a leaking needle valve. Although I would think that unlikely since the OP said he was unable to restart the engine after it ran for 15 minutes.
Is it even worth fixing with an internal issue like crank bearings, etc?
Really guy, you need more knowledge before trying to work on this. If you can't fix a Briggs single, you need more library time.I do aerospace engineering, not gas engine engineering. That's why I'm here, because I don't know how everything about how to troubleshoot a gas engine and I thought I might get some help. I haven't really heard any good explanations for my problem, though. I'll head over to a different forum, and likely just bring the thing in for repair.