I have a '95 John Deere 38 STX lawn tractor. Just went through it 2 weeks ago. Cleaned the mower deck, sharpened the blades, changed the oil, cleaned the spark plug and replaced the air filter. After that, I just "touched the key" and it fired right up! Next time out, it started a little hard. Yesterday, the motor would crank, but it never fired. I found that the plug wire was loose, but upon re-attachment, it still would not start. I called the local John Deere dealer and they said that the Kolher 12.5 engines are famous for having starting problems and that it "may" be the ignition module ($ 62.), but he wasn't sure. For them to inspect it would be another $85. more, and they could not look at it for 2 weeks! How can I tell and where is the "ignition module"? FYI - I bought a new spark plug (as I can't remember ever replacing it), but have not installed it yet.

20HP V twin Any common or known issues for these seizing up? Have on in the shop and it simply does not want to turn over. I was able to get it to turn far enough to verify both pistons are moving up and down. Also pulled the flywheel and all is intact and the engine still does not want to turn with flywheel removed. The crank under the flywheel had about 1/2" of pretty well built up rust and the upper bearing (what is exposed any way) looked fairly well molded up as in much moisture...(Pac NW is common for this white stuff on equipment left out) I have serviced this GT for several years now and it has always been only the usual, belts and mandrels and such. Never has used a drop of oil. Comments when it quit was that it was running, got off to put the dogs up and it just quit...quietly :o