Initial Inspection and Diagnostic Overview
COMMUTATORCommutator:
1. Place the armature in a pair of "V" blocks and check the runout with a dial indicator.
Standard value: 0.05 mm (0.002 in.)
Limit: 0.1 mm (0.004 in.)
Commutator:
2. Measure the commutator outer diameter.
Standard value: 32.0 mm (1.260 in.)
Limit: 31.0 mm (1.220 in.)
Standard value: 29.4 mm (1.158 in.)
Limit: 28.8 mm (1.118 in.)
Commutator:
3. Check the undercut depth between segments.
Standard value: 0.5 mm (0.020 in.)
FIELD COIL OPEN-CIRCUIT TEST (Direct drive type only)
Check the continuity between field brushes. If there is continuity, the field coil is in order.
FIELD COIL GROUND TEST (Direct drive type only)
Check the continuity between field coil brush and yoke. If there is no continuity, the field coil is free from grounding.
Brush Holder:
BRUSH HOLDER CHECK
Check the continuity between brush holder plate and brush holder.
If there is no continuity, the brush holder is in order.
OVERRUNNING CLUTCH
1. While holding clutch housing, rotate the pinion. Drive pinion should rotate smoothly in one direction, but should not rotate in opposite direction. If clutch does not function properly, replace overrunning clutch assembly.
2. Inspect pinion for wear or burrs. If pinion is worn or burred, replace overrunning clutch assembly. If pinion is damaged, also inspect ring gear for wear or burrs.
FRONT AND REAR BRACKET BUSHING
Inspect bushing for wear or burrs. If bushing is worn or burred, replace front bracket assembly or rear bracket assembly.