It sounds to me like something is heat soaking after the engine is stopped, meaning that something that normally gets some cooling air from the engine's rotation is overheating once the engine stops spinning. Doesn't the coil get cooled by the air coming off the fins on the flywheel? If so, then either it's failing slowly or maybe the screen above the flywheel opening is clogged with leaves and grass. I doubt the second, because I have to assume that the shops you took it to would clean that off as a matter of course. So I'm betting the coil is heat soaking after the engine shuts down and stops cooling it.

We retired and moved from Toronto to a lake in cottage country NE of Kingston Ontario in 1998. I bought the previous owners 14 HP YT 5700 which at that time was only a few years old. His requirements were quite minimal and consequently the tractor was in excellent condition. I wanted to turn what had been about 4 acres of field into lawn to give the property an estate look but 14 HP was inadequate so I bought an 18 HP Simplicity and so the Yamaha has been sitting in the garage for about 10 years. A problem had developed around the time I bought the Simplicity which is that whenever I turned off the tractor it wouldn't start again until it had cooled down. I'm a technopeasant so I didn't know what the problem was but locals told me it was probably the coil. At any rate since I have my Simplicity the Yamaha is useless to me but would be a gem for a mechanically minded person. Any suggestions as to what the problem might be? I would be tempted to keep it if it can be easily fixed but also would consider selling it to any interested person. I think $300 would be a good price but am open to realistic offers from anybody out there. I have a utility trailer so delivery could be negotiated. I can be reached at Canadave@ripnet.com or at(613) 387-2976. This is the first time I've been to this terrific site for several years. The first time was when I was looking for a bigger HP tractor and I bought a Simplicity Conquest with the Vanguard engine because of the recommendations here. It has been an excellent tractor and has worked flawlessly ever since. The only problem I had was the engine blowing as a consequence of mice getting into it over the winter which wasn't the tractor's fault. Again because of this site I was directed to a place where I could save several hundred dollars on a new engine where I did and actually got a 20 HP replacement. I hope I'll hear from someone soon. Thanx guys

Tomplum is spot on there. I have repaired "worst case" problems (where plastic connector melts or breaks) by replacing the connector assembly with individual, insulated wire spade terminals. But using the individual terminals means you have to be absolutely certain you understand exactly where each wire is supposed to go. To release a spade terminal from the connector body, insert a small screwdriver into the business end of the connector (in the direction indicated by red arrow) to depress the locking tab that secures the terminal to a lock notch in the plastic. While holding the locking tab down with the release tool (screwdriver), gently pull on the wire at the back end of the connector. If the release tool is in place properly, and the connector is not melted, the wire and terminal will slip easily out of the connector. I have also had success with just cleaning and tightening the terminal by ever so slightly closing the gap of the terminal with a small pair of pliers. Cleaning can be done using a small, stiff sliver of sand paper inserted into the open end of the terminal, but it requires patience.If the terminal has a dark or blackish appearance, don't even try to clean it.....it has been hot and is no good now. Replace it.

Hi, I'm "fredmertz" today is Dec. 6 2022 AD. I just got the 22 y.o. Toro CCR 2000 out of the crawl space, fresh gas and started on the second pull. Ran for twenty minutes, shut it off, restarted on the first pull. They don't make them like this anymore.