Testing the Inspection.

TM5-4110-234-14

TO 40R7-5-7-1

(1) Testing the Armature for Shorts: Place the armature in a growler and hold a thin steel blade parallel to the

core and just above it, while slowly rotating the armature in the growler (fig. 5-24). A shorted armature causes the blade

to vibrate and move toward the core. A shorted armature must be replaced.

Figure 5-24. Test for Shorted Armature F10000RG-2

(2) Testing Armature for Grounds: Touch armature shaft or core and the end of each commutator bar with a pair

of ohmmeter leads (fig. 5-25). If the ohmmeter reading is low, it indicates a grounded armature. Replace armature.

Figure 5-25. Test for Grounded Armature F10000RG-2

5-45