90cc Alpha Sports Kolt - Had it for about 6 years. Never had to do anything but clean carb and adjust brakes. Runs well, but discovered recently that, if throttle is depressed while in neutral, the engine will rev high and cannot be killed with switch, key or even by removing spark plug wire. I think the throttle may be sticking, but has anyone ever heard of engine continuing to run even after it is switched off and plug wire pulled? How is this possible?

 

Heat..Does the motor feel extremely hot when this happens?

 

Haven't checked but I'm sure it is hot. Also, since this happened (yesterday), I've had to kick start it. Electric start does nothing. It kicks starts easily and runs/idles smoothly, but electric start was working before this problem.

 

The engine is shut off by removing spark. But you say that even removing the spark plug wire doesn't shut it off. Dieseling is the only thing left. Something is too hot in the combustion chamber that is firing the mixture on compression.

 

Makes sense. I had thought about that possibility, but I didn't realize it could happen, especially in a small engine. I guess I'll start with changing the oil and making sure engine is clean.

 

Maybe check the pipe also.

 

Good idea. I definitely will. Thanks.