Just put 30 hours on new M4-71, parked it for lunch, now the tractor wont start. The battery has 12.8 v, the oil is good, when you turn the key to on or start you can hear the fuel pump running but to power to the starter. Dead. checked all the fuses, all good. The transmission and shift lever are in "N" and the park brake is on. I'm really baffled. Help.