ELECTRIC STARTING SYSTEM

ELEC

+

INSPECTION AND REPAIR

1.Check:

Commutator

Dirt Clean with 600 grit sandpaper.

2.Measure:

Commutator diameter a

Out of specification Replace the starter motor.

Min. commutator diameter

16.6mm (0.65 in)

3.Measure:

Mica undercut a

Out of specification Scrape the mica to the proper measurement with a hacksaw blade which has been grounded to fit the commutator.

Mica undercut 1.5 mm (0.06 in)

NOTE:

The mica must be undercut to ensure proper operation of the commutator.

4.Measure:

Armature assembly resistances (com-

mutator and insulation)

Out of specification Replace the starter motor.

Measure the armature assembly resis- tances with the pocket tester.

Pocket tester

YU-03112-C/90890-03112

Armature assembly Commutator resistance 1

0.0117 ~ 0.0143 at 20 ˚C

(68 ˚F)

Insulation resistance 2 Above 1 Mat 20˚C (68 ˚F)

If any resistance is out of specification, replace the starter motor.

6 - 14

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Image 307
Yamaha WR45OFR service manual Inspection and Repair, Min. commutator diameter 16.6 mm 0.65, Mica undercut 1.5 mm 0.06