Charge Air Cooler (Cac) Leakage; Cooling Fan Drive Mechanism; Drive Pulley And Universal Joint Shaft; Idler Replacement - PREVOST H3-41 Maintenance Manual

SECTION 05A: H3 SERIES COOLING SYSTEM
FIGURE 34: REMOVING UPPER FAN DRIVE SUPPORT
BRACKET
21. With assistance, remove fan drive and drive
frame from radiator.
22. Remove fan shroud from radiator.
FIGURE 35: REMOVING FAN SHROUD FROM RADIATOR
Reverse removal procedure to reinstall radiator
assembly.
12 CHARGE AIR COOLER (CAC)
LEAKAGE
Spec for CAC acceptable leakage: The CAC is
considered acceptable if it can hold 30 psi (206
kPa) gauge pressure with not more than 5 psi
(34 kPa) loss in 15 seconds after turning off the
hand valve.
NOTE
This spec does not apply if there is any
evidence that the leak was caused by a
foreign object impact.
13

COOLING FAN DRIVE MECHANISM

13.1 DRIVE PULLEY AND UNIVERSAL
JOINT SHAFT
To disconnect the universal shaft, proceed as
follow:
WARNING
Set the ignition to the OFF position and
remove the key from the contact switch to
prevent accidental starting of the engine.
24 PA1621 Maintenance Manual All Series | January 2017
1. Unwrap the drive belt from around the pulley
(see paragraph MOUNTING THE DRIVE
BELT).
2. Dismount the fan drive pulley. Gain access to
the 6 mounting bolts from behind the pulley,
through the opening in the cast aluminum
support (Figure 37).
3. Unscrew and remove the universal joint shaft
mounting bolts (6) at the fan clutch.
4. Slowly, move the shaft toward the rear of the
vehicle.
5. Finally, dismount the universal joint shaft
from the fan drive pulley (6 bolts).
Installation of the universal joint shaft is the
same as removal, but in reverse order.
FIGURE 36: COOLING FAN DRIVE MECHANISM
FIGURE 37: DISMOUNTING FAN DRIVE PULLEY
13.2

IDLER REPLACEMENT

If an idler is defective, replace as follow:
05149
05123C