John Deere 3020 12 Volt Wiring Diagram. If starter is a true 12 volt model 24 volts will fry it aka make toast of the field coil. Made a battery box to fit on the tractor side frame and used one 1000 amp 12 volt battery.
The electrical system used on john deere diesel tractors with electric start is a 24 volt split load system. Wrg 9599 john deere 3020 starter wiring diagram. New 12 volt starter, 12 volt 1 wire alternator, alternator mounting bracket, battery cables & wiring, solenoid & instruction sheet cross ref with part numbers: