Chrysler Conquest 1988 Service Manual page 963

Tension pulley
Crankshaft pulley
2OY160(
AIR CONDITIONING - Service Adjustment Procedures 24-87
COMPRESSOR DRIVE BELT ADJUSTMENT
N24FJAA
Satisfactory performance of the air-conditioning system is
dependent upon drive belt condition and tension. If the proper
tensions are not maintained, belt slippage will greatly reduce
air-conditioning performance and drive belt life. To avoid such
adverse effects, the following service procedure should be
followed:
(1) Any belt that has operated for a minimum of one half-hour is
considered to be a "used" belt. Adjust air-conditioning drive
belt at the time of new-car preparation.
(2) Check drive belt tension at regular service 'intervals and
adjust as needed.
Standard value: 17 - 20 mm (.7 - .8 in.)
COMPRESSOR NOISE
N24FLAA
When investigating an air-conditioning related noise, you must
first know the conditions when the noise occurs. These
conditions are: weather, vehicle speed, in gear or neutral,
engine temperature or any other special conditions.
Noises that develop during air-conditioning operation can often
be misleading. For example: what sounds like a failed front
bearing or connecting rod, may be caused by loose bolts, nuts,
mounting brackets, or a loose clutch assembly. Verify acces-
sory drive belt tension (power steering, alternator or air pump).
Improper accessory drive belt tension can cause a misleading
noise when the compressor is engaged and little or no noise
when the compressor is disengaged.
Drive belts are speed sensitive. That is, at different engine
speeds, and depending upon belt tension, belts can develop
unusual noises that are often mistaken for mechanical prob-
lems within the compressor.
ADJUSTMENT PROCEDURES
(1) Select a quiet area for testing. Duplicate conditions as much
as possible. Switch compressor on and off several times to
clearly identify compressor noise.
To duplicate high ambient conditions (high head pressure),
restrict air flow through condenser. Install manifold gauge
set to make sure discharge pressure doesn't exceed 2,070
kPa (300 psi).
(2) Tighten all compressor mounting bolts, clutch mounting
bolt, and compressor drive belt. Check to assure clutch coil
is tight (no rotation or wobble).
(3) Check refrigerant hoses for rubbing or interference that can
cause unusual noises.
(4) Check refrigerant charge (see "Charging the System").
(5) Recheck compressor noise as in Step 1.
(6) If noise still exists, loosen compressor mounting bolts and
retorque. Repeat Step 1.
(7)
If noise continues, replace compressor and repeat Step I.