Commutator Inspection
- Inspect commutator for dirt or signs of burning. If dirt or burning is present, sand lightly with No. 300-400 sand paper or lathe as necessary to clean surface.
- Using a dial indicator, check commutator for runout. Maximum runout is .015" (.4 mm). If runout exceeds the maximum limit, replace commutator.
- Using a micrometer, measure diameter of brush end of commutator. Minimum measurement is 1.063"(27 mm). If measurement is less than minimum, replace commutator.
- Measure depth of grooves between commutator segments and insulators. See Fig 1. Minimum depth is .008" (.2 mm). If less than minimum depth, replace commutator.