Mitsubishi Montero (2002-2004). Manual — part 64

ON-VEHICLE SERVICE

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-119

COMPRESSOR DRIVE BELT ADJUSTMENT

M1552001000131

Refer to GROUP 00, Maintenance Service

− Drive Belts

P.00-

39

.

CHARGING

M1552001200276

Use the refrigerant recovery station to charge the refrigerant.

METHOD BY USING REFRIGERANT RECOVERY
AND RECYCLING UNIT

Using the refrigerant recovery and recycling unit, refill the
refrigerant.
NOTE: Refer to the Refrigerant Recovery and Recycling Unit
Instruction Manual for operation of the unit.

DISCHARGING SYSTEM

Use the refrigerant recovery unit to discharge refrigerant gas
from the system.
NOTE: Refer to the Refrigerant Recovery and Recycling Unit
Instruction Manual for operation of the unit.

REFILLING OF OIL IN THE A/C SYSTEM

Too little oil will provide inadequate compressor lubrication and
cause a compressor failure. Too much oil will increase dis-
charge air temperature.
When a compressor is installed at the factory, it contains 120
cm

3

(4.1 floz) of refrigerant oil. While the A/C system is in oper-

ation, the oil is carried through the entire system by the refriger-
ant. Some of this oil will be trapped and retained in various
parts of the system.
When the following system components are replaced, it is nec-
essary to add oil to the system to replace the oil being removed
with the component.

Compressor oil: SUN PAG 56
Quantity:

• Evaporator: 60 cm

3

(2.0 floz)

• Condenser: 15 cm

3

(0.5 floz)

• Suction hose: 10 cm

3

(0.3 floz)

• Receiver: 10 cm

3

(0.3 floz)

ON-VEHICLE SERVICE

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HEATER, AIR CONDITIONING AND VENTILATION

55A-120

PERFORMANCE TEST

M1554008800026

1. The vehicles to be tested should be in a place that is not in

direct sunlight.

2. Close the high and low-pressure valve of the gauge

manifold.

3. Connect the charging hose (blue) to the low-pressure valve

and connect the charging hose (red) to the high-pressure
valve of the gauge manifold.

4. Install the quick joint (for low-pressure) to the charging hose

(blue), and connect the quick joint (for high-pressure) to the
charging hose (red).

CAUTION

• To connect the quick joint, press section A firmly

against the service valve until a click is heard.

• When connecting, run your hand along the hose while

pressing to ensure that there are no bends in the hose.

5. Connect the quick joint (for low-pressure) to the low-

pressure service valve and connect the quick joint (for high-
pressure) to the high-pressure service valve.
NOTE: The high-pressure service valve is on A/C pipe and
the low-pressure service valve is on the suction hose.

6. Start the engine.
7. Set the A/C controls as follows:

<Testing the front-A/C>

• A/C switch: A/C − ON position

• Mode selection: FACE position

• Temperature control: MAXIMUM COOLING position

• Air selection: RECIRCULATION position

• Blower switch: FAST position

8. Set the A/C controls as follows:

<Testing the rear-A/C>

• The front A/C should be set as described in step 7.

• A/C switch: A/C-ON position

• Temperature control: MAXIMUM COOLING position

• Blower switch: FAST position

9. Adjust engine speed to 1,500 r/min with A/C clutch engaged.
10.Engine should be warmed up with doors and windows

closed.

AC001388

LOW-PRESSURE
VALVE

HIGH-PRESSURE
VALVE

GAUGE MANIFOLD

CHARGING
HOSE (RED)

A

SLEEVE

CHARGING
HOSE (BLUE)

ADAPTOR
VALVE
(FOR
LOW-PRES-
SURE)

ADAPTOR
VALVE
(FOR HIGH-
PRESSURE)

LOW-
PRESSURE
SERVICE
VALVE

HIGH-
PRESSURE
SERVICE
VALVE

AB

ON-VEHICLE SERVICE

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HEATER, AIR CONDITIONING AND VENTILATION

55A-121

11.Insert a thermistor-type thermometer into the air vent shown

in the figure, and measure the air temperature.

12.Note the discharge air temperature.

NOTE: If the clutch cycles, take the reading before the
clutch disengages.

Performance Temperature Chart <Front-A/C test>

Performance Temperature Chart <Rear-A/C test>

REFRIGERANT LEAK REPAIR

M1552001500125

LOST CHARGE

If the system has lost all charge due to a leak:
1. Evacuate the system. (See procedure.)
2. Charge the system with approximately 0.453 kg (1

pound) of refrigerant.

3. Check for leaks.
4. Discharge the system.
5. Repair leaks.

ACX01485 AB

THERMOMETER

AC002699AB

THERMOMETER

GARAGE AMBIENT
TEMPERATURE

°C (°F)

20 (68)

25 (77)

35 (95)

40 (104)

Discharge air
temperature

°C (°F)

3.5

− 5.5 (38 − 42) 3.5 − 5.5 (38 − 42) 4.5 − 6.5 (40 − 44) 5.5 − 7.5 (42 − 46)

Compressor high
pressure kPa (psi)

1,050

− 1,250 (152

− 181)

1,050

− 1,250 (152

− 181)

1,400

− 1,600 (203

− 232)

1,650

− 1,850 (239

− 268)

Compressor low
pressure kPa (psi)

120

− 140 (17 −

20)

120

− 140 (17 −

20)

130

− 150 (19 −

22)

160

− 180 (23 −

26)

GARAGE AMBIENT
TEMPERATURE

°C (°F)

20 (68)

25 (77)

35 (95)

40 (104)

Discharge air
temperature

°C (°F)

5.5

− 7.5 (42 − 46) 5.5 − 7.5 (42 − 46) 6.5 − 8.5 (44 − 47) 7.5 − 9.5 (46 − 49)

Compressor high
pressure kPa (psi)

1,150

− 1,350 (167

− 196)

1,150

− 1,350 (167

− 196)

1,500

− 1,700 (218

− 247)

1,750

− 1,950 (254

− 283)

Compressor low
pressure kPa (psi)

130

− 150 (19 −

22)

130

− 150 (19 −

22)

140

− 160 (20 −

23)

180

− 200 (26 −

29)

ON-VEHICLE SERVICE

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HEATER, AIR CONDITIONING AND VENTILATION

55A-122

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 refriger-
ant. If it is possible to repair the leak without dis-
charging 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 sys-
tem when it is opened for repair or replacement of
lines or components. The following precautions must
be observed. The system must be completely dis-
charged 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 (3.1 inches) from the exhaust mani-
fold. 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

M1552008700120

.

You must first know the conditions when the noise occurs.
These conditions are: weather, vehicle speed, in gear or neu-
tral, 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 generator). Improper accessory drive belt
tension can cause a misleading noise when the compressor is
engaged and little or no noise when the compressor is disen-
gaged. 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 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).