sounds like a bad switch. There is a magnetic switch on the prop hub. Take the spark plug out turn the batt switch on and turn the prop. you should see a blue spark. If you dont try passing a magnet across the sensor. The magnet in the prop hub could be demagnatized. sounds like a bad switch. There is a magnetic switch on the prop hub. Take the spark plug out turn the batt switch on and turn the prop. you should see a blue spark. If you don't try passing a magnet across the sensor. The magnet in the prop hub could be demagnetized