Armature Inspection And Test
- Remove the starter.
- Disassemble the starter as shown at the beginning of this procedure.
- Inspect the armature for wear or damage from contact with the permanent magnet. If there is wear or damage, replace the armature.
- Check the commutator (A) surface. If the surface is dirty or burnt, resurface with emery cloth or a lathe within the following specifications, or recondition with #500 or #600 sandpaper (B).
- Measure the commutator (A) runout.
- If the commutator runout is within the service limit, check the commutator for carbon dust or brass chips between the segments.
- If the commutator run out is not within the service limit, replace the armature.
Commutator runout
Standard (New): 0.05 mm (0.0019 in.) max
Service limit: 0.08 mm (0.0031 in.)
- Check the mica depth (A). If the mica is too high (B), undercut the mica with a hacksaw blade to the proper depth. Cut away all the mica (C) between the commutator segments. The undercut should not be too shallow, too narrow, or v-shaped (D).
Commutator mica depth
Standard (New): 0.8 mm (0.314 in.)
Limit: 0.2 mm (0.0079 in.)
- Check for continuity between the segments of the commutator. If an open circuit exists between any segments, replace the armature.
- Check with an ohmmeter that no continuity exists between the commutator (A) and armature coil core (B), and between the commutator and armature shaft (C). If continuity exists, replace the armature.