Find the wire coming from the ignition switch to the starter solenoid. Set a volt ohm meter to DC voltage. Secure the black lead to a clean part of the frame. Attach the red lead to the wire coming from the ignition switch to the starter solenoid. Turn the ignition key to the start position. Did the Ohm meter register 12 or more volts. If yes the solenoid is bad. If no then the switch is not sending the necessary voltage to the starter. If a lack of voltage is detected connect a jumper wire to the positive battery post. Make sure the tractor is in neutral with the brakes on. Turn the ignition key to the run position. Touch the jumper wire connected to the positive post of the battery to the post on the solenoid the wire coming from the ignition switch connects to. Did the starter engage and spin the engine over? Yes - No. if yes look at the switch. If no look at the starter and solenoid.
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