ENGINE DIVISION SERVICE MANUAL
Fig. 12. Testing Armature for Grounds
If the commutator is worn, dirty or out-of-round
or the insulation is high, the commutator should
be turned down and under cut.
Field Coils - Check field coils for ground and
opens with a test lamp.
Grounds - With the field coil ground
disconnected, position one test prod on the
field frame and the other to the field
connector. If the lamp lights the field coils
are grounded and must either be replaced
Opens - If the test lamp does not light when
the prods are connected to the ends of coil
leads, the field coils are open.
A pole shoe spreader and pole shoe screw
driver should be used if the field coils are to be removed.
Extra caution should be taken in replacing the field coils
to prevent grounding or shorting when they are tightened
in place. If the pole shoe has a long lip on one side, it
should be assembled in the direction of armature
Four kinds of clutches or motor drives
(a heavy duty sprag, a Positork drive, an intermediate
duty type and a splined drive) may be used on the
enclosed shift lever heavy duty motors.
The intermediate clutch may be either the sprag
type or the four roll type. All four types are moved into
mesh with the flywheel ring gear by action of the
solenoid. The pinion will remain engaged until starting is
assured and the solenoid is interrupted.
Intermediate Duty Sprag Clutch
Remove the lock wire, collar and spring from
sleeve assembly. Early design type cluthes are
equipped with a spring stop and a second lock
wire which must be removed after removing the
Remove the retainer ring and large washers. DO
NOT remove sleeve assembly or sprags from
Lubricate the sprags and saturate the felt washer
with No. 5W-20 oil. Heavier oil must not be used.
Reassembly is the reverse of the disassembly.
CGES-230 - Page 13