QuestionQUESTION: I have simplicity sunstar 18 hp tractor .the motor runs fine until after about 20 minutes under load the engine will shut off. I can wait till it cools off about an hour or more and it will refire and run fine for another 20 minutes and shut down again.you can leave mower with pto on and it will not shut down it will only shut down when mowing. I have replaced seal in motor 'changed oil sending unit,,bypassed circit breaker, when mower shuta down there is no fire on plugs. motor will turn over but will not start.thank you randy duckworth in carolina
ANSWER: What is the model number of your Kohler engine? You can download the service manual from Kohler...for free!
In cases like yours the first thing I would do is isolate the engine igntion system from the mower wire harness. This usually just involves dis-connecting one wire...just need the engine model number to help you find the one wire.
Eric
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QUESTION: Kohler Magnum 20, Model Number M20S
Serial Number is 2129008036
Spec number 49544
AnswerService manual can be found at the address below:
http://www.kohlerengines.com/onlinecatalog/pdf/tp_2204_b.pdf
Page 8.3 describes how to check the ignition module but you have to remove the engine sheet metal to access the module.
An easier way to isolate the ignition module from the mower chasis is locate the kill lead wire connected to the engine. There will be a wire from the ignition module to a terminal on the engine. The terminal allows the mower manufacturer a place to connect the shut-off wire. It is usually only ONE wire and either a spade or screw terminal.
I would dis-connect this wire and use the mower. NOTE you will NOT be able to shut-off the mower with the kill-lead dis-connected. You can just close the choke and flood the engine to turn it off or you could pull each spark plug wire to stop the engine...I'd use the choke.
Let me know if the mower will run more than 20 minutes with the kill-lead dis-connected.
Thanks.
Eric
