Starter Motor: Testing and Inspection

Repair or replace necessary parts if extreme wear or damage is found during inspection.

Armature




Check for continuity between commutator and segment. Replace commutator if there is no continuity (i.e., disconnected).




Check for continuity between commutator and shaft. Also, check for continuity between commutator and armature core,armature core and shaft. Replace commutator if there is continuity (i.e., internally grounded).

Brush
Measure the length of brush.
Replace with a new one, if it is below the limit.

Brush Holder




Check for continuity between brush holder (+) (4) and base (-). Replace, if there is continuity (i.e., insulation is broken).

Magnetic Switch




Check for continuity of shunt coil between terminals S and M.
Replace, if there is no continuity (i.e., coil is disconnected).

Continuity of Series Coil




Check for continuity between terminals S and M. Replace, if there is no continuity (i.e., coil is disconnected).

Continuity of Contacts




With the plunger faced downward, push down the magnetic switch. In this state, check for continuity between terminals B and M. Replace, if there is no continuity (i.e., contacts are faulty).

Pinion




Check if the pinion rotates smoothly in drive direction by hand, or if it is locked when it is rotated in reverse. If not, replace the pinion.

Characteristic Test




For easily confirming the characteristics, conduct the no-load test as follows:

Rating as short as 30 seconds requires rapid testing.

Fix the starter on the test bench, and wire as shown in illustration. When the switch is closed, the current flows and the starter runs under no load. At this time, measure current, voltage and speed to check if they satisfy the standard.