Compressor Belts; Belt Replacement - Central System - PREVOST H3-41 Maintenance Manual

For air conditioning unit, ball valves are added
on supply and return lines in the condenser
compartment. They
evacuate the A/C overhead compartment circuit.
When work has to be done on an evaporator coil
unit, it will be easier to remove it and repair it on
a bench.
FIGURE 23: OVERHEAD COMPARTMENT FAN AIR
FILTER
3.6

COMPRESSOR BELTS

3.6.1 Belt Replacement – Central System
Set the main battery disconnect switch to the
OFF position. For greater safety, set the
engine rear starter selector switch in engine
compartment to the OFF position.
1. Open engine compartment rear door and
locate A/C compressor drive belt tensioner.
Loosen tensioner screw to release belt
tension.
2. For vehicles equipped with a 3
belt tensioning is also applied through air
bellows (Figure 25). Turn the belt tensioner
two-way control valve counterclockwise to
release bellows pressure (Figure 27).
3. Remove the radiator fan drive belt (refer to
Section 05 COOLING).
4. Slip the old compressor belts off and the
new ones on.
have service port
22201
DANGER
alternator,
rd
PA1621 Maintenance Manual All Series | Revised February 2019
SECTION 22: HEATING AND AIR CONDITIONING
NOTE
Both belts
to
simultaneously to ensure an equal distribution
of load on each of them.
Twin BX71 belt proper tension
New: 90-100 lbs
Used: 75-85 lbs
Belt tension Tool:7770002
FIGURE 24: STANDARD BELT LAYOUT WITH CENTRAL
HVAC SYSTEM
Single 5VX740 belt proper tension
New: 150-160 lbs
Used: 120-130 lbs
Belt tension Tool:7770002
Single 5VX940 belt to 3rd alternator proper tension
Automatic with pneumatic bellows
FIGURE 25: H3 SERIES BELT LAYOUT W/ 3RD ALT.
NOTE
Belts specifications may vary. For proper belt
selection, always consult your vehicle Coach
Final Record.
MAINTENANCE
A/C compressor drive belt
Clean belt tension, inspect for cracks or
frayed material at the intervals specified by
the Lubrication And Servicing Schedule in
Section 24: LUBRICATION & SERVICING.
must always be replaced
23