I went to start the tractor today and it just quit trying to crank. I took the starter off and put a battery charger on it. I put the ground on the body and the red on the lug then used a screw driver to jump over to the small tab. it clicked out and ran like it was suppose to. I put it back in the tractor. I checked voltage at the battery...12.7. at the big lug on the starter...12.7. both with the key off. I turn the key on and turn the start button and nothing happens. so I check the voltage at the starter when I turn the start button and the voltage drops to .02vts. I checked the starter small terminal and it shows its grounded. is it suppose to be? any ideas will be great thanks.