ARMY TM 9-2815-259-24
AIR FORCE TO 38G1-125-2
MARINE CORPS 09249A/09246A-24
(13) Check and replace starter components.
Check armature commutator run-out as follows (Refer to Figure 4-21):
FIGURE 4-21. CHECKING COMMUTATOR RUN-OUT
(1) Place armature bearings on V-blocks.
(2) Zero dial indicator on commutator.
(3) Rotate armature and record run-out. Standard is 0.0008 inch (0.02 mm), with a limit
of 0.00197 inch (0.5 mm).
(b) Using a micrometer, measure outer diameter of commutator. If measurement is less than
1.38 inches (35 mm), replace armature. Refer to Figure 4-22.
FIGURE 4-22. MEASURING COMMUTATOR OD