Doosan DX60R Shop Manual page 406

Cleaning and Inspection
Armature
Commutator Surface Inspection
if the commutator is rough, polish the surface with a #500 to
#600 emery cloth (Figure 353).
Measure Commutator Outside diameter
Measure Commutator Outside diameter (Figure 354). Replace
the armature if the measurement is less than the limit.
See "Starter Motor Specifications" on page -220 for the service
limit.
Measure Commutator Insulation Depth
Measure the depth of the insulating material (1, Figure 355)
between commutator segments (2, Figure 355). If the depth
measures less than the limit, use a hacksaw blade (3, Figure
355) to remove the insulating material until the depth is within
the limit.
A normal commutator condition is indicated in (4, Figure 355).
An abnormal commutator condition is indicated in (5, Figure
355).
See "Starter Motor Specifications" on page -220 for the service
limit.
Engine
Page 226
Figure 353
Figure 354
Figure 355
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