Mitsubishi S4Q2 User Manual

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Service Manual Mitsubishi SQ-Series diesel engines
Version 08/2004
STARTER
ENGLISH
ELECTRICAL SYSTEM
3. Inspecting commutator
1) Support the armature in V-blocks and
measure the runout of the commutator with a
dial indicator. If the runout is near the service
limit, recondition the commutator, making sure
the commutator diameter does not exceed the
service limit which is 31.4 mm [1.236 in.].
If the commutator surface is rough, smoothen
it with a sandpaper of #300 to #500.
Unit: mm [in.]
2) Measure the diameter of commutator. If it is
smaller than the service limit, replace the
armature.
Unit: mm [in.]
3) Measure the depth of each mold between
segments with a depth gauge. If the depth is
less than the repair limit, recondition the mold.
Unit: mm [in.]
27.4.2 Field Coil
1. Testing for open circuits
If there is no continuity between the lead wire and
positive (+) brush, the field coil is open and the
yoke assembly should be replaced.
Item Service Limit
Runout of commutator 0.1 [0.004]
Item Normal Size Service Limit
Diameter of
commutator
32
[1.26]
31.4
[1.236]
Segment
BadGood
Mold depth
Item
Assembly
Standard
Service Limit
Depth of
commutator mold
0.4 to 0.6
[0.016 to 0.024]
0.2 [0.008] or
less

Mitsubishi S4Q2 Specifications

General

Brand	Mitsubishi
Model	S4Q2
Category	Engine
Language	English