Drive Pinion; Brushes And Springs; Commutator Mica Inspection; Checking Armature - Kohler CH18-745 Service Manual

Kohler Engine Parts Call K&T 606-678-9623 or 606-561-4983
Section 8
Electrical System and Components
Inspection

Drive Pinion

Check and inspect the following areas:
a. The pinion teeth for abnormal wear or damage.
b. The surface between the pinion and the clutch
mechanism for nicks, or irregularities which could
cause seal damage.
c. Check the drive clutch by holding the clutch
housing and rotating the pinion. The pinion should
rotate in one direction only.

Brushes and Springs

Inspect both the springs and brushes for wear, fatigue,
or damage. Measure the length of each brush. The
minimum length for each brush is 7.6 mm (0.300 in.).
See Figure 8-52. Replace the brushes if they are worn
undersize, or their condition is questionable.
Wear limit length:
7.6 mm (0.300 in.)
Figure 8-52. Checking Brushes.
Armature
1. Clean and inspect the commutator (outer
surface). The mica insulation must be lower than
the commutator bars (undercut) to ensure proper
operation of the commutator. See Figure 8-53.
8.32
Commutator O.D.
Mica Insulation
Figure 8-53. Commutator Mica Inspection.
2. Use an ohmmeter set to the Rx1 scale. Touch the
probes between two different segments of the
commutator, and check for continuity. See Figure
8-54. Test all the segments. Continuity must exist
between all or the armature is bad.
Insulation
Check
Armature
Coil
Figure 8-54. Checking Armature.
3. Check for continuity between the armature coil
segments and the commutator segments. See
Figure 8-54. There should be no continuity. If
continuity exists between any two, the armature is
bad.
4. Check the armature windings/insulation for
shorting.
Shift Fork
Check that the shift fork is complete, and the pivot and
contact areas are not excessively worn, cracked or
broken.
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Continuity Check