I grew up on a 4230 JD (the 100HP ag tractor) and I read the owner's manual front back and sideways and I don't recall any automated shutdowns other than me pulling out the fuel shutoff knob.....no electronic controls back then, the only safety feature was an alert operator. In fact you could start the tractor, turn the ignition back to 'off' and the engine would run until you pulled out the fuel stop.....