Starter Motor Assembly - Yamaha YFM250XL(C) Service Manual

ELECTRIC STARTING SYSTEM
STARTER MOTOR INSPECTION
1.Inspect:
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 measure-
ment using a hacksaw blade which has
been grounded to fit the commutator.
4.Inspect:
Armature coil (insulation/continuity)
Defects → Replace the starter motor.
*********************************
Armature coil inspection steps:
Connect the pocket tester for the continu-
ity check 1 and insulation check 2.
Measure the armature resistances.
If the resistance is incorrect, replace the
starter motor.
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ELEC
Outside diameter:
28 mm (1.10 in)
<Wear limit:>
27 mm (1.06 in)
Mica undercut:
0.7 mm (0.028 in)
Armature coil resistance:
Continuity check 1:
0.004 ~ 0.005 Ω at 20 ˚C (68 ˚F)
Insulation check 2:
More than 1 MΩ at 20 ˚C (68 ˚F)
– +
8