S-71
05-E3B, 05-E3BG, WSM
DIESEL ENGINE
Commutator and Mica
1. Check the contact of the commutator for wear, and grind the
commutator with emery paper if it is slightly worn.
2. Measure the commutator O.D. with an outside micrometer at
several points.
3. If the minimum O.D. is less than the allowable limit, replace the
armature.
4. If the difference of the O.D.'s exceeds the allowable limit, correct
the commutator on a lathe to the factory specification.
5. Measure the mica undercut.
6. If the undercut is less than the allowable limit, correct it with a saw
blade and chamfer the segment edges.
W1155802
Brush Wear
1. If the connect face of the brush is dirty or dusty, clean it with
emery paper.
2. Measure the brush length (A) with vernier caliper.
3. If the length is than the allowable limit, replace the yoke assembly
and brush holder.
W1156360
Commutator
O.D.
Factory
spec.
Electromagnetic
drive type
28.0 mm
1.10 in.
Gear reduction
type
30.0 mm
1.18 in.
Allowable
limit
Electromagnetic
drive type
27.0 mm
1.06 in.
Gear reduction
type
29.0 mm
1.14 in.
Difference of
O.D.’s
Factory
spec.
Electromagnetic
drive type
Less than 0.05 mm
0.002 in.
Gear reduction
type
Less than 0.02 mm
0.0008 in.
Allowable
limit
Electromagnetic
drive type
0.4 mm
0.02 in.
Gear reduction
type
0.05 mm
0.002 in.
Mica under cut
Factory spec.
0.50 to 0.80 mm
0.020 to 0.031 in.
Allowable limit
0.20 mm
0.0079 in.
(1) Segment
(2) Depth of Mica
(3) Mica
(a) Correct
(b) Incorrect
Brush length A
Factory spec.
16.0 mm
0.630 in.
Allowable limit
10.5 mm
0.413 in.
KiSC issued 12, 2007 A