user manual

7-20
ELEC
ELECTRIC STARTING SYSTEM
NOTE:
EAS00769
Checking The Starter Motor
1. Check:
S commutator
Dirt  Clean with 600 grit sandpaper.
2. Measure:
S commutator diameter
a
Out of specification  Replace the starter
motor.
Min. commutator diameter
27 mm
3. Measure:
S mica undercut
a
Out of specification  Scrape the mica to the
proper measurement with a hacksaw blade
which has been grounded to fit the commuta-
tor.
Mica undercut
0.7 mm
The mica must be undercut to ensure proper
operation of the commutator.
4. Measure:
S armature assembly resistances (commuta-
tor and insulation)
Out of specification  Replace the starter
motor.
a. Measure the armature assembly resistances
with the pocket tester.
Pocket tester
90890-03112
Armature assembly
Commutator resistance
1
0.025 X 0.035 Ω at 20_C
Insulation resistance
2
Above 1 MΩ at 20_C
b. If any resistance is out of specification, re-
place the starter motor.