Chevrolet Light Duty Truck 1973 Service Manual page 415

WORKING CHAMBER v
ARM
PUMP PLATE
CIRCULATING HOLES
WIPER
7—
Fig. Fan Clutch Pump Plate
i| S
_
- F------ / CLUTCH PLATE
A W I I B 1 ' W
Fig. 6—Automatic Fan Clutch
4.
A. Start with a cool engine to ensure complete fan
C. Use dial type thermometer, J6742-01, or similar
E N G I N E C O O L I N G
.BALL BEARING
_
^
BIMETALLIC COIL
ENGINE OVERHEATING
clutch disengagement. Refer to Item b, paragraph
1
.
B. If the fan and clutch assembly free-wheels with no
drag (revolves over 5 times when spun by hand),
the clutch should be replaced. If clutch performs
properly with a slight drag go to step C.
NOTE: Testing a fan clutch by holding the
small hub with one hand and rotating the
aluminum housing in a clockwise/counter­
clockwise motion will cause the clutch to free­
wheel, which is a normal condition when
operated in this manner. This should not be
considered a test by which replacement is
determined.
type.
NOTE: J6742-01 reads to 180 degrees F,
therefore, allow approximately 3/16" pointer
movement for each 10 degrees over 180
degrees
Check for adequate clearance
CAUTION:
6 K -5
FLUID RESERVOIR CHAMBER
LIGHT DUTY TRUCK SERVICE MANUAL