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ELEC
ELECTRIC STARTING SYSTEM
CHECKING THE STARTER MOTOR
1. Check:
• commutator
Dirty
→
Clean it with #600 grit sandpaper.
2. Measure:
• commutator diameter
a
Out of specification
→
Replace the starter
motor.
3. Measure:
• mica undercut
b
Out of specification
→
Scrape the mica
using a hacksaw blade.
NOTE:
Scrape the mica to the proper measurement
using a hacksaw blade which has been
grounded to fit the commutator.
Outside diameter
28 mm (1.10 in)
<Wear limit>:
27 mm (1.06 in)
Mica undercut
0.7 mm (0.03 in)
4. Check:
• armature coil (insulation/continuity)
Defects
→
Replace the starter motor.
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a. Connect the pocket tester for the continuity
check
1
and insulation check
2
.
b. Measure the armature resistances.
c. If the resistance is incorrect, replace the
starter motor.
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Armature coil resistance
Continuity check
0.025 ~ 0.035
Ω
at 20 °C (68 °F)
Insulation check
More than 1 M
Ω
at 20 °C (68 °F)
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