Inspection And Maintenance; Armature - Komatsu 4D98 Series Shop Manual

9. Starting Motor
9.1.5 Inspection and Maintenance
(1) Armature
(a) Commutator outside diameter
Measure the commutator outside diam-
eter and replace the commutator if the
measured value is less than the limit.
(b) Armature coil continuity test
Check continuity between commutator
segments with a multimeter. Good if
continuity exists.
m
(Coil disconnection)
Replace the armature.
(c) Armature coil insulation test
Inspect the continuity between a com-
mutator segment and the shaft or core
with a multimeter. Good if no continuity
exists.
[Continuityexists
(Coil short circuit)
Replace the armature.
Fig. 10
1
Muttimeter
Fig. 11
Fig. 12
9-8