Starter Armature: Testing and Inspection

Armature




1. Check continuity between commutator and core with ohmmeter. Replace armature if there is continuity.




2. Check continuity between commutator and shaft with ohmmeter. Replace armature if there is continuity.




3. Place armature on V-blocks, and measure runout with a dial indicator. If runout is not within specification, repair armature with a lathe or replace armature.

Run out: 0.002 in (0.05 mm)
Maximum: 0.016 in (0.4 mm)

4. Replace armature if diameter of commutator is at, or less than, grind limit.

Grind limit: 1.22 in (31 mm)




5. It commutator surface is dirty, wipe it with a cloth; if it is rough, repair it with a lathe or fine sandpaper.




6. Replace armature if depth of mold between segments is at, or less than, minimum.

Depth: 0.02 - 0.03 in (0.5 - 0.8 mm)
Minimum: 0.008 in (0.2 mm)