on the case (fig. 110). Rotate the armature slowly through a complete revolution. If a short circuit is
present, the steel strip will become magnetized and vibrate. Replace the armature if shorted.
(i) Inspect the bearing journals on both sides of the armature shaft for wear, scoring, and pitting. Replace
the armature if the journals are excessively worn.
(j) Inspect the armature shaft keyway and key for burrs, cracks, and pitting. If necessary, smooth the
surfaces with a small, fine-cut file or carborundum stone.
(k) Inspect the drive pulley and fan for cracks, breaks, warpage, and broken or damaged fan blades.
Replace the fan if the blades are broken or if the body is cracked or warped.
Figure 110. Testing armature for short circuit on growler.
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