TM 10-3930-664-24 6. Measure armature shaft and bore clearance as follows: a. Measure I.D.  of shaft bore in magnetic switch assembly. b. Measure O.D.  of armature shaft. c. Subtract shaft O.D.  from bore I.D.  (A - B).  Service limit is 0.2 MM. 7. Inspect brush holder for damage to brushes or springs. Check insulation for deterioration.  Replace brushes if less than 2/3 original length. 8. Using multimeter, conduct brush holder continuity test. If there  is  continuity, replace brush holder. 9. Using multimeter, conduct yoke winding continuity test.  There shall be continuity. 10.  Inspect  clutch  pinion  to  ensure  free movement in direction of starter rotation.  Clutch shall lock if pinion is rotated in opposite direction. 3-99 TM 10-3930-664-24