Chevrolet Light Duty Truck 1973 Service Manual page 420

6 K - 1 0 E N G IN E C O O L IN G
Fig. 12—Securing Fan Blade
movement. This represents the total radial run-out.
Mark the point on the pulley at which the highest
reading is obtained.
4. If the total indicator reading is less than .006 inch,
the assembly is within specification. Install fan belt
and adjust.
If the total indicator run-out exceeds .006 inch, proceed
to Step 5.
5. Divide the total indicator reading in half and
obtain this thickness from shim stock (1/2 x 3/4)
and resork per Figure 8. Place this shim pack
between the water pump pulley and fan clutch hub
at the bolt closest to the point marked on the pulley
in Step 3. If the mark on the pulley is between two
bolts so that it is difficult to determine which bolt is
closest, place two shim packs; one under each bolt
on either side of the mark. (See Figure 15.)
B o lt Torque S equ en ce
a. When one shim pack is used, first, torque the
bolt over which the shim pack has been placed;
second, the bolt opposite the first; and finally,
the other two. Recommended torque is 25 lbs. ft.
Fig. 13 —Checking Run-Out
b. When two shim packs are used, each bolt must
be torqued partially; then to full torque
alternating between opposite bolts; then the
other two bolts in the same manner. Recom­
mended torque is 25 lbs. ft.
NOTE: Excessive run-out may result if the
above sequence and recommended torque is
not used.
6. Recheck total indicator run-out to verify that run­
out is within .006 inch. Install fan belt and adjust.
Water Pump
Removal
If you siphon coolant from the
WARNING:
radiator, do not use mouth to start siphoning
action. The coolant solution is POISONOUS
and can cause death or serious illness if
swallowed.
LIGHT DUTY TRUCK SERVICE MANUAL