I agree with JD3520Turbo. The fuel shutoff solenoid is located on the back of the injection pump on the right side of the engine block. It is probably still painted black because it may have never been replaced. The first thing to look for is if the paint is peeling up on the solenoid and you can see the gold colored metal, then it is probably overheating due to a short in the solenoid itself. Another thing you can check is turn the keyswitch on the "Acc" position just before "Crank" and listen for a noticable "click" on the solenoid. Feel free to put your finger on the solenoid while doing this and you should be able to feel the shuttle valve inside move upon turning the key switch. If the solenoid does not click, it is either the solenoid itself or the keyswitch is not getting power or not transfering power. Since the tractor is turning over, all of the safety switches must be performing correctly and the keyswitch is getting power to the starter solenoid, but it may not be getting to the fuel shutoff solenoid on the injection pump. Let me know what you find.
