If you switch a tractor to 12 volt that has a magneto, it probably won't start until you let off of the starter, and it slows down enough for the impulse to work. Was odd until we figured out what was going on. We've got a W-6 that is 6 volt with a mag. Two pulls on the crank and it fires right up, no battery needed. It was the tractor I used for my little projects, my gas was safe, nobody else wanted to crank it.