Note: Before diagnosing the starter, make sure the battery is fully charged.
1. If the starter does not turn when the key is turned to the third position, make sure the gear shift lever is in neutral.
2. Check the tightness of the cables from the battery to the starter and starter solenoid.
3. If the starter rotates but the engine does not, the overrunning clutch is slipping: replace the starter.
4. If the solenoid turns on (clicking sound), but the starter does not rotate, perhaps the internal contacts of the solenoid are burnt out, or there is a seizure in the engine.
5. If you cannot hear the solenoid turning on, either the battery is bad, or the solenoid is defective, or the solenoid turning circuit is broken.
6. To check the solenoid, connect its small electrical terminal to the positive battery terminal. If the starter works, then the problem is in the lock or wiring.
7. If the starter does not work, remove and repair the solenoid.
8. If the engine rotates abnormally slowly with the starter, check the battery contamination and the tightness of the contact connections. If everything is OK with this, the oil is too thick or there is a partial seizure in the engine.
9. Start the engine and warm it up to operating temperature. Disconnect the distributor center wire and ground it to ground.
10. Connect the voltmeter to the battery terminals (observe polarity).
11. Crank the engine (no more than 15 sec. at a time!) and read the voltmeter readings. At normal engine speed and voltmeter readings over 9 volts, the starter is OK. If the voltmeter readings over 9 volts, but the engine rotates slowly, there are problems with the engine. If the voltage recorded by the voltmeter is less than 9 volts with slow engine rotation, there are problems with the starter, the battery is discharged, bad contacts, burnt solenoid contacts.