ARMY TM 9-2815-256-24
AIR FORCE TO 38G1-96-2
MARINE CORPS TM 2815-24/5
FIGURE 3-27. Measuring Commutator OD
Measure commutator segment mica depth as shown in FIGURE 3-28. If depth is less than 0.0079 inch (0.2
mm), undercut the mica.
FIGURE 3-28. Measuring Segment Mica Depth
Check commutator surface for bum spots. This usually indicates an open circuit. Remove these spots using
#400 abrasive paper.
Inspect bearings (34 and 35, FIGURE 3-15) for wear and damage. If damaged or worn replace bearings using a
press, refer to FIGURE 3-29.