ARMY TM 9-2815-260-24 AIR FORCE TO 38G1-126-2 MARINE CORPS TM 09244A/09245A-24 4-29 (13) Check and replace starter components. (a) 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 OD 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