Failure of the engine to turn over

The most common problem is worn solenoid contacts. They can be replaced separately but most people just replace the entire starter. This always starts out as an intermittent problem, and it will crank if you cycle the ignition switch to "crank" enough times.

Any testing for this problem must be done while the problem is acting up, and it usually will not act up during a bench-test off the engine because there is no load on it and it will draw very little current. That means the worn contacts don't have to work very hard to pass enough current for the motor to spin.

Caradiodoc