tire pressure MITSUBISHI ECLIPSE 1991 Owner's Manual

24-24 HEATERS AND AIR CONDITIONING - Service Adjustment Procedures
COMPRESSOR NOISENUFIABWhen 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 oftenbe 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, or alternator).
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 coilis tight (no rotation or wobble).
(3) Check refrigerant hoses for rubbing or interference that cancause 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 1.
Condenser fan motor relay,
Magnet clutch
relay, Blower
motor High
relayHeater relayML0312
16W908
POWER RELAY CHECKNUFNAE
NOTEFor information concerning the installation position of each
relay, refer to
P.24-8.CONDENSER FAN MOTOR RELAY, MAGNET CLUTCH
RELAY, BLOWER MOTOR HIGH RELAY, HEATER RELAY
Check for continuity between the terminals when- the battery
power-supply is applied to terminal (2). and terminal (4) is
grounded.
1 When current flows 1 Between terminals l-3 1 Continuity1
I
When no currentBetween terminals l-3 No continuity
flowsBetween terminals 2-4 Continuity
IKinks in the refrigerant tubing or sharp bends in the
Never attempt to rebend formed lines to fit. Use the
refrigerant hose lines will greatly reduce the
capac-correct line for the installation you are servicing.
ity of the entire system. High pressures are
pro-A good rule for the flexible hose lines is keep the
duced in the system when it is operating. Extreme
radius of all bends at least 10 times the diameter of
care must be exercised to make sure that all
the hose.
connections are pressure tight. Dirt and moisture
Sharper bends will reduce the flow of refrigerant.
can enter the system when it is opened for repair or
The flexible hose lines should be routed so that theyreplacement of lines or components. The following
are at least 80 mm (3 in.) from the exhaust manifold.precautions must be observed.
It is good practice to inspect all flexible hose lines atThe system must be completely discharged before
least once a year to make sure they are in good
opening any fitting of connection in the refrigeration
condition and properly routed.
Fsystem. Open fittings with caution even after the
Unified plumbing connections with O-rings. These
4’system has been discharged. If any pressure is
noticed as a fitting is loosened, allow trappedO-rings are not reusable.
pressure to bleed off very slowly.