Isuzu AA-6HK1T, Workshop Manual

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6D3–16 STARTING AND CHARGING
Inspection and Repair
Armature
1. Use a circuit tester to check armature continuity.
Hold the circuit tester probes against 2 commutator
segments. Repeat the procedure for several other
segment pairs.
There must be continuity between all commutator
segments. If there is not, the commutator must be
replaced.
2. Use a circuit tester to check the armature ground.
Hold one probe against a commutator segment. Hold
the other probe against the armature shaft.
If there is continuity, the armature is grounded. It
must be replaced.
3. Measure the commutator outside diameter.
4. If the measured diameter is less than the specified
limit, the commutator must be replaced.
Commutator outside diameter
Standard: 32 mm (1.28 in)
Limit: 31.4 mm (1.256 in)
5. Inspect the commutator mica segments for
excessive wear and damage.
6. Measure the depth of the commutator mica
segments.
If the depth is less than the specifed limit, the
commutator must be replaced.
Commutator mica segment depth
Standard: 0.5 mm (0.02 in)
Limit: 0.2 mm (0.008 in)