I've read several threads on this issue but mine problems are bigger and 'different.' Engine starts even when I am not sitting on the chair and even when in gear. Not safe! But will not shut off with the key. The fuel stop solenoid works fine when I put 12 volts on it, but what confuses me is that 12 volts EXTENDS the pin of the solenoid that shuts off the engine, which I can also do with my finger when the solenoid is out. So 12 volts to the solenoid is designed to STOP the engine! One question is "where does the 12 volts to activate the fuel stop solenoid normally come from when one shuts off the ignition?" A mystery. Then, to add to my confusion, the wiring diagram in the Kubota repair manual shows THREE wires to the solenoid, but my tractor has only two. More confusion. Finally, the repair manual says that a bad solenoid causes the tractor to not shut off (mine works fine..just like the new one I bought.) But the manual also says a bad 20 A fuse will have the same effect. So I checked the 20 A fuse, it was bad, and I was so excited to have found the solution. But, alas, putting in a good 20 A fuse...no change/same issue...won't shut off, but now even the gas gauge doesn't work, which is was doing when I had a bad 20 A fuse. Can anyone help me sort through what I should do next? THANKS!!