BONNET AS 1260106 - Caterpillar

Engines With Electric StartersSeveral things can cause starters to remain engaged after the engine is running. Indications that this has occured include: 1. Worn bearings in the starter drive assembly.2. Starter drive teeth are badly worn on the reverse side.3. Armature commutator has exploded.4. Discoloration of the starter end cap.5. Solenoid coils are open, or shorted windings.
If the above symptoms are observed, the starter is not usually at fault. Check for one or more of the following problems. 1. Stuck or sticking dash mounted start switch (most probable).2. Stuck or sticking solenoid contacts (check battery).3. Stuck or sticking starter relay (if applicable).4. Failure of the wiring harness, battery positive to start circuit, anywhere between the start switch and the starter solenoid.5. Loose and/or incorrectly positioned wiring on the solenoid. This can cause the solenoid to engage the starter.