Mitsubishi MOTORS Lancer 2004, Руководство по ремонту

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ON-VEHICLE SERVICE
HEATER, AIR CONDITIONER AND VENTILATION 55-74
REFRIGERANT LEAK REPAIR
PROCEDURE
M1552001500277
LOST CHARGE
If the system has lost all charge due to a leak:
1. Evacuate the system (Refer to
P.55-72 ).
2. Charge the system with approximately 480
−
520
g of refrigerant.
3. Check for leaks.
4. Discharge the system.
5. Repair leaks.
CAUTION
Replacement filter-drier units must be sealed
while in storage. The drier used in these units will
saturate water quickly upon exposure to the
atmosphere. When installing a drier, have all
tools and supplies ready for quick assembly to
avoid keeping the system open any longer than
necessary.
6. Replace receiver drier.
7. Evacuate and charge system.
LOW CHARGE
If the system has not lost all of its refrigerant charge;
locate and repair all leaks. If it is necessary to
increase the system pressure to find the leak
(because of an especially low charge) add
refrigerant. If it is possible to repair the leak without
discharging the refrigerant system, use the
procedure for correcting low refrigerant level.
HANDLING TUBING AND FITTINGS
Kinks in the refrigerant tubing or sharp bends in the
refrigerant hose lines will greatly reduce the capacity
of the entire system. High pressures are produced in
the system when it is operating. Extreme care must
be exercised to make sure that all connections are
pressure tight. Dirt and moisture can enter the
system when it is opened for repair or replacement of
lines or components. The following precautions must
be observed. The system must be completely
discharged before opening any fitting of connection
in the refrigeration system. Open fittings with caution
even after the system has been discharged. If any
pressure is noticed as a fitting is loosened, allow
trapped pressure to bleed off very slowly.
Never attempt to rebend formed lines to fit. Use the
correct line for the installation you are servicing. A
good rule for the flexible hose lines is keep the radius
of all bends at least 10 times the diameter of the
hose.
Sharper bends will reduce the flow of refrigerant. The
flexible hose lines should be routed so that they are
at least 80 mm from the exhaust manifold. It is good
practice to inspect all flexible hose lines at least once
a year to make sure they are in good condition and
properly routed.
On standard plumbing fittings with O-rings, these
O-rings are not reusable.
COMPRESSOR NOISE CHECK
M1552008700272
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 A/C 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 accessory 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 problems within the
compressor.
ADJUSTMENT
1. Select a quiet area for testing. Duplicate
conditions as much as possible. Switch the
compressor on and off several times to clearly
identify compressor noise. To duplicate high
ambient conditions (high head pressure), restrict
air flow through the condenser. Install a manifold
gauge set to make sure discharge pressure
doesn't exceed 2,070 kPa.
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 (Refer to P.55-69 ).
5. Recheck compressor noise as in Step 1.
6. If noise still exists, loosen compressor mounting
bolts and retighten. Repeat Step 1.
7. If noise continues, replace compressor and repeat
Step 1.