Just discovered this forum. Have posted on several other forums and received some responses but this forum seems to be loaded with Kohler experts! My engine is on a Gravely 18-H garden tractor (basically an Ariens GT 18 with a Gravely paint job). I use it to mow 1.5 acres and blow snow. It is 18 years old with about 12-1400 hours. The hourmeter broke in the first couple years so I am giving my best estimate. Engine starts and runs great. Burns very little oil. Compression is 100 & 105 psi. The only work I have done so far is one new exhaust valve/seat and new voltage rectifier, both a few years ago. I wouldn't be thinking about doing anything except crankshaft endplay is excessive at 0.025" compared to the spec of 0.002/0.014". This winter I am planning on tearing her down to install a new thrust washer. I have been advised to replace the governor gear and install new rings. One person suggested a complete overhaul. I will need this tractor for only another 3-5 years. I would appreciate any tear down tips and/or advice about what I should do when I get in there. Thanks.