Chevrolet CHEVY VAN G10 SERIES Service Manual page 309

WINDSHIELD WIPER AND WASHER
G eneral D e s c rip tio n .............................................................. .... 12-9
Principal o f O peration ............................................................ 12-9
D iagnosis-W iper on V e h i c l e .............................................. .... 12-11
Service O perations .............................................................. .... 12-11
Wiper M otor ......................................................................... 12-11
Rem oval and I n s ta lla tio n ............................................... 12-11
D isassem bly ...................................................................... 12-13
The wiper m o to r assembly consists o f com pound w ound 12
volt D.C. m otor, gear reduction mechanism and parking switch
enclosed in a com m on die cast housing. The arm ature has a
worm shaft w hich drives a gear and shaft assembly. A crank
arm , w hich is attached externally to the gear shaft, operates
the linkage which activates the blades.
The wiper m o to r is equipped w ith an internal circuit
breaker m o u n ted on th e m otor brush plate which protects the
m o to r from overheating.
Figure 12 shows th e assembly o f th e washer pum p to the
wiper m otor.
PRINCIPLE OF OPERATION
(ELECTRICAL CIRCUITS)
The following facts should be kept in mind.
1. The wiper dash switch is a grounding type switch and,
therefore, m ust be securely m ounted.
2. When installed in a vehicle, the wiper m o to r is connected
to the chassis thru a ground strap. This in effect connects
the wiper housing to the ground side of the battery.
A L IG N IN G PIN
Fig. 1 2 —Washer Mechanism Mounting on W iper
INDEX
Page
GENERAL DESCRIPTION
3. The ignition switch opens and closes the feed wire circuit
dash control switch and a parking switch located in the wiper
m o to r gear box.
opened by a cam on the gear w hen the wiper blades reach the
park position. The park switch acts as a holding switch to
m aintain the m o to r circuits to ground during that period of
operation betw een the tim e th e op erato r turns the wiper o ff at
the dash switch and the blades reach the park position. Figure
13 shows the park switch contacts open.
Turning the Wiper "O N "—"L O " Speed
(Assume Ignition Switch On)
or " LO" speed position, the w iper m o to r circuits are com-
E L E C T R IC A L -B O D Y A N D CHASSIS 12-9
Inspection .....................................................................
Reassem bly ..................................................................
A d ju s tm e n ts ..................................................................
Windshield Washer Pum p Assembly
R e m o v a l- r e p la c e m e n t..............................................
Valve Assembly R e p la c e m e n t.................................
to the wiper, therefore, it m ust be turned "ON" to
operate wipers.
The wiper m o to r operation is controlled by two sw itch es-a
The parking switch contacts are norm ally closed and are
When the operator turns the wiper dash switch to the " ON"
Fig. 1 3 —Gear in P A R K Position—Contacts Open
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12-15
12-18
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12-19
12-19
C H E V Y V A N S H O P M A N U A L