Starter Bearing: Testing and Inspection
INSPECT COMMUTATORa. Check the commutator for the dirty and burnt surfaces.
If the surface is dirty or burnt, correct it with sandpaper (No.400) or on a lathe.
b. Check for the commutator circle runout.
1. Place the commutator on V-blocks.
2. Using a dial gauge, measure the circle runout.
Maximum circle runout: 0.05 mm (0.0020 in.)
If the circle runout is greater than maximum, correct it on a lathe.
c. Using vernier calipers, measure the commutator diameter.
Standard diameter: 30.0 mm (1.181 in.)
Minimum diameter: 29.0 mm (1.142 in.)
If the diameter is less than minimum, replace the armature.
d. Check that the undercut depth is clean and free of foreign materials. Smooth out the edge.
Standard undercut depth: 0.6 mm (0.024 in.)
Minimum undercut depth: 0.2 mm (0.008 in.)
If the undercut depth is less than minimum, correct it with a hacksaw blade.
INSPECT BEARING
Turn the bearing by hand while applying inward force.
If resistance is felt or the bearing sticks, replace the bearing.