GMC 4000 Series Service Manual page 34

10 Gear Box Housing
1 Nut
11 Brush Plate Assy, and
2 Crank Arm
3 Seal Cap
12 Brushes
4 Retaining Ring
13 Wave Washers
5 Washer
6 Gear Box Cover
7 Output Gear and
Shaft Assy.
8 Intermediate Gear
9 Wave Washer
Motor
8. Remove motor through bolts, tap motor
frame lightly, and separate motor assembly from
gear box housing.
9. Remove brush tension by placing brush
spring in holder groove as shown in figure 13.
10. Slide armature and end plate from motor
frame and field. Note arrangement of wave wash­
ers (fig. 14) on gear end of armature shaft before
removing to assure proper installation upon motor
assembly.
11. Pull end plate from armature. Note thrust
plug between tip of armature shaft and end plate.
INSPECTION
Check armature shaft, gears, and supporting
bushings for wear. Inspect commutator for evi­
dence of arcing or loose solder joints to armature
windings. Check "PARK" contacts for dirt or oxi­
dation. Inspect for worn brushes, weak springs,
and binding in holders.
In general, inspect all parts for serviceability
and replace as required. All parts can be replaced
individually except motor frame and field which is
serviced as an assembly. Service kits provide all
necessary attaching parts for installation of gear
cover and terminal board.
ASSEMBLY (Fig. 12)
Motor
Reassemble motor using reverse order of
G M C S E R V I C E M A N U A L
Mounting Brackets
14 Flat Washers
15 Armature
16 Thrust Plug
Figure 12— Wiper Motor and Gear Box Assem bly (Typical)
GENERAL MAINTENANCE
17 Frame and Field
18 End Plate
19 Tie Bolts
"Disassembly" procedures.
NOTE: Be sure wave washers on armature
shaft are installed properly as shown in figure 14.
Lightly lubricate armature shaft bushings with
light machine oil. Be sure brushes are properly
positioned in holders before armature commutator
protrudes between brushes.
Gear Box
1. Assemble gear box in reverse order of
"Disassembly" procedures.
NOTE: Lubricate gear teeth with Delco Cam
and Ball Bearing Lubricant or equivalent. Be sure
cover is properly located over dowel pins and that
BRUSH HOLDER
REMOVE BRUSH SPRING FROM SLOT
A N D PLACE IT IN GROOVE AS SH O W N
Figure 13— Releasing Brush Spring Tension
Sec. 1
Page 27
(Two Required)
T-3642