2007 ISUZU KB P190 suction

1-34 HEATER AND AIR CONDITIONING

REFRIGERANT RECYCLING
Recycle the refrigerant recovered by ACR4 or equivalent.
For the details of the actual operation, follow the steps in the
ACR
4 Manufacturer's Instructions.
ACR4 (115V 60Hz) :5-8840-0629-0 (J-39500-A)
ACR4 (220-240V 50/60Hz)
: 5-8840-0630-0 (J-39500-220A)
ACR
4 (220-240V 50/60Hz Australian model)
: 5-8840-0631-0 (J-39500-220ANZ)

F06R300014


EVACUATION OF THE REFRIGERANT
SYSTEM
NOTE:
Explained below is a method using a vacuum pump. Refer
to the ACR
4 (or equivalent) Manufacturer's Instructions
when evacuating the system with ACR4 (or equivalent).

Air and moisture in the refrigerant will cause problems in the air
conditioning system.
Therefore, before charging the refrigerant, be sure to evacuate
air and moisture thoroughly from the system.
1) Connect the gauge manifold. •
••
•
High-pressure valve (HI) - Discharge-side
•
••
•
Low-pressure valve (LOW ) - Suction-side
2) Discharge and recover the refrigerant.
3) Connect the center hose of the gauge manifold set to the vacuum pump inlet.
4) Operate the vacuum pump, open shutoff valve and then open both hand valves.
5) W hen the low-pressure gauge indicates approx. 100kPa (750 mmHg/30 inHg), continue the evacuation for 5 minutes
or more.
6) Close both hand valves and stop the vacuum pump.


7) Check to ensure that the pressure does not change after 10
minutes or more. •
••
•
If the pressure changes, check the system for leaks.
•
••
•
If leaks occur, retighten the refrigerant line connections
and repeat the evacuation steps.
8) If no leaks are found, again operate the vacuum pump for 20 minutes or more. After confirming that the gauge
manifold pressure is at 100 kPa (750 mmHg/30 inHg), close
both hand valves.
9) Close positive shutoff valve.
Stop the vacuum pump and disconnect the center hose from the vacuum pump.


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ISUZU KB P190 2007

1-90 HEATER AND AIR CONDITIONING
f06r300014
CHECKING REFRIGERANT SYSTEM
WITH MANIFOLD GAUGE
Conditions;
• Ambient temperature at approx. 30 ∼35 °C (86 ∼95 °F)
• Run the engine at Idling
• A/C switch is “ON”
• Run the blower motor at “4” (high) position
• Temperature control knob sets at “MAX COLD”
• Air source selector lever at “CIRC”
• Close the all doors
Normal pressures kPa (kg/cm
2 /psi);
Low-pressure side: Approx. 127 – 245 (1.3 – 2.5 / 18 – 36)
High-pressure side: Approx. 1373 – 1670 (14 – 17 / 199 – 242)
Connect the manifold gauge
Low-pressure hose (LOW ) ∼ Suction side
High-pressure hose (HI) ∼ Discharge side



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HEATER AND AIR CONDITIONING 1-91
RESULT SYMPTOM TROUBLE CAUSE CORRECTION
Reduced or no air flow through
the condenser
•
Condenser clogged or dirty
• Radiator (condenser) fan
does not operate properly •
Clean
• Check cooling fan
operation
No bubbles in sight glass when
condenser is cooled by water
(Insufficient cooling)



•
Excessive refrigerant in
system




•
Check sight glass.
(See “Reading Sight
Glass”)
• Discharge and
recover refrigerant.
Recharge to specified
amount
Discharge
(High)
pressure
gauge
abnormally
high
After stopping air conditioning,
pressure drops approx. 196 kPa
(2.0kg/cm
2 / 28psi) quickly •
Air in system
•
Evacuate and charge
refrigerant system
Insufficient cooling and excessive
bubbles in the sight glass





•
Insufficient refrigerant in
system





•
Check sight glass.
(See “Reading Sight
Glass”)
• Check for leaks
• Discharge and
recover refrigerant.
Recharge to specified
amount
Low pressure gauge indicates
vacuum •
Clogged or defective
expansion valve •
Replace the
expansion valve
Frost or dew on refrigerant line
before and after receiver/ drier or
expansion valve, and low pres-
sure gauge indicates vacuum •
Restriction caused by debris
or moisture in receiver/drier

•
Check system for
restriction and
replace receiver/drier

Discharge
(High)
pressure
gauge
abnormally
low
After turning off air conditioning,
high and low pressure gauge
balanced quickly
•
Compressor seal defective
• Poor compression due to
defective compressor
gasket •
Replace or repair
compressor
Low pressure gauge is lowered
after condenser is cooled by
water
•
Excessive refrigerant in
system

•
Discharge and
recover refrigerant
Recharge to specified
amount
Low pressure hose temperature
around the compressor refrigerant
line connector is lower than
around evaporator

•
Unsatisfactory valve
operation due to defective
temperature sensor of
expansion valve
• Expansion valve opens too
long •
Replace the
expansion valve




After turning off air conditioning,
high and low pressure gauge is
balanced quickly •
Compressor gasket is
defective
•
Replace


Suction
(Low)
pressure
gauge
abnormally
high
Air conditioning turns off before
passenger compartment is
sufficiently
cool •
Electronic thermostat
defective
•
Check the electronic
thermostat and
replace as necessary


* For the charging and discharging operations in the table above, refer to “RECOVERY, RECYCLING,
EVACUATION AND CHARGING” in this section.

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ISUZU KB P190 2007

1-92 HEATER AND AIR CONDITIONING
RESULT SYMPTOM TROUBLE CAUSE CORRECTION
Condenser is not hot and
excessive bubble in sight glass





•
Insufficient refrigerant






•
Check sight
glass.(See “Reading
Sight Glass”)
• Check for leaks
• Discharge and
recover refrigerant.
Recharge to specified
amount
Frost on the expansion valve inlet
line •
Expansion valve clogged
•
Replace the
expansion valve
A distinct difference in
temperature between the inlet and
outlet refrigerant lines of the
receiver/drier •
Receiver/drier clogged


•
Replace the receiver/
drier


Expansion valve outlet refrigerant
line is not cold and low-pressure
gauge indicates vacuum

•
The temperature sensor of
the expansion valve is
defective, and the valve
cannot regulate the correct
flow of the refrigerant •
Replace the
expansion valve



Discharge temperature is low and
air flow from vents is restricted
•
Frozen evaporator core fins

•
Check electronic
thermostat and
replace as necessary
Suction
(Low)
pressure
abnormally
low

Low-pressure gauge reading is
low, or a vacuum reading may be
shown •
Clogged or blocked
refrigerant line
•
Replace refrigerant
line
No bubbles in sight glass after
condenser is cooled by water
(Insufficient cooling)



•
Excessive refrigerant in
system




•
Check sight
glass.(See “Reading
Sight Glass”)
• Discharge and
recover refrigerant.
Recharge to specified
amount
Reduce air flow through con-
denser
•
Condenser clogged
• Radiator (condenser) fan
does not rotate properly •
Clean
• Check cooling fan
operation
Suction
(Low) and
Discharge
(High)
pressure
abnor-
mally
high

Suction (Low) pressure hose is
not cold •
Air in system • Evacuate and charge
refrigerant
Suction
(Low) and
Discharge
(High)
pres-sure
abnor-
mally
low Insufficient cooling and excessive
bubbles in the sight glass •
Insufficient refrigerant in
system
•
Check sight glass.
(See “Reading Sight
Glass”)
• Check for leaks
• Discharge and
recover refrigerant.
Recharge to specified
amount

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ISUZU KB P190 2007

POWER-ASSISTED STEERING SYSTEM 3B-17
Power Steering Pump (4JH1-TC, 4JA1-T)
Power Steering Pump and Associated Parts


RTW 53BMF000401
Legend (1) Pump Assembly
(2) Suction Hose
(3) Flexible Hose
(4) Bolt
(5) Bracket


Removal
1. Remove the drive belt.
2. Remove the pulley
3. Place a drain pan below the pump.
4. Disconnect the suction hose.
5. Disconnect the flexible hose.
6. Remove the power steering fixing bolt and remove the pump assembly.

Installation
1. Install the pump assembly to the pump braket,
tighten the fixing bolt to the specified torque.
Torque: 40 N·m (4.1 kgf·m/30 lb·ft)
2. Install the flexible hose.
Tighten the nut to specified torque.
Torque: 20 N·m (2.0 kgf·m/14 lb·ft)
3. Install the pulley and tighten the bolt to the specified torque.
Torque: 28 N·m (2.9 kgf·m/21 lb·ft)
4. Install the drive belt.
5. Connect the suction hose, then fill and bleed system.
Refer to Bleeding the Power Steering System in this section.

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3B-18 POWER-ASSISTED STEERING SYSTEM
Power Steering Pump Disassembled View






RTW 63BLF000301
Legend
(1) Bolt
(2) Suction Pipe
(3) O-ring
(4) Shaft Assembly
(5) Oil Seal
(6) Front Housing
(7) O-ring
(8) O-ring
(9) Side Plate
(10) Rotor and Vane
(11) Cam
(12) Pump Cartridge Assembly
(13) O-ring
(14) Snap Ring
(15) Rear Housing
(16) Bolt
(17) Spring
(18) Relief Valve
(19) O-ring
(20) Connector
(21) Bush
(22) Pulley
(23) O-ring




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POWER-ASSISTED STEERING SYSTEM 3B-19
Disassembly
1. Clean the oil pump with solvent (plug the discharge
and suction ports to prevent the entry of solvent).
Be careful not to expose the oil seal of shaft
assembly to solvent.
2. Remove the bolt, suction pipe and O-ring.
3. Remove the connector, O-ring, relief valve and spring.
4. Remove the bolt, rear housing and O-ring.
5. Remove the snap ring.
6. Remove the shaft assembly.
7. Remove the oil seal.
CAUTION: When removing the oil seal, be careful
not to damage the housing.
8. Remove the pump cartridge assembly from the front housing.
9. Remove two O-rings.

Inspection and Repair
Make all necessary adjustments, repairs, and part
replacements if wear, damage, or other problems are
discovered during inspection.

Rotor
442RS002
Check that the groove in the vane is free from excessive
wear and that the vane slides smoothly. W hen part
replacement becomes necessary, the pump cartridge
should be replaced as a subassembly.



Vane
442RS003
Sliding faces of the vane should be free from wear.
(Particularly the curved face at the tip that contact with
the cam should be free from wear and distortion). W hen
part replacement becomes necessary, the pump
cartridge should be replaced as a subassembly.

Cam
The inner face of the cam should have a uniform
contact pattern without a sign of step wear. W hen part
replacement becomes necessary, the pump cartridge
should be replaced as a subassembly.

Side Plate
The sliding faces of parts must be free from step wear
(more than 0.01 mm (0.0004 in)), which can be felt b
y
the finger nail.
The parts with minor scores may be reused after lapping
the face.

Relief Valve
The sliding face of the valve must be free from burrs
and damage. The parts with minor scores may be
reused after smoothing with emery cloth (#800 or finer).

Shaft
Oil seal sliding faces must be free from a step wear
which can be felt by the finger nail. Bushing fitting face
must be free from damage and wear.

O-ring, Oil Seal, Snap Ring
Be sure to discard used parts, and always use new
parts for installation. Prior to installation, lubricate all
seals and rings with power steering fluid.


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ISUZU KB P190 2007

3B-20 POWER-ASSISTED STEERING SYSTEM
Reassembly
1. Install oil seal to front housing. Be sure to discard
used oil seal, and always use new parts fo
r
installation.
CAUTION: When installing the oil seal, be careful
not to damage the oil seal contacting surface of the
housing.
2. Install shaft assembly.
3. Install the vanes to roter with curved face in contact with the inner wall of cam.
442RS005
4. Install roter and vanes to cam.
5. Install pin to front housing.
6. Install two new O-rings to front housing. Be sure to discard used O-ring.
7. Install side plate.
CAUTION: When installing side plate, be careful not
to damage its inner surface. Damaged side plate
may cause poor pump performance, pump seizure
or oil leakage.
8. Install pump cartridge assembly to front housing.
9. Install snap ring to shaft end.
10. Install rear housing with a new O-ring. Be sure to discard used O-ring. Then install bolt and tighten it
to specified torque.
Torque: 25 N ･
･･
･
m (2.5 kgf ･
･･
･
m/18 lb ･
･･
･
ft)
11. Install suction pipe with a new O-ring. Be sure to discard used O-ring. Then install bolt and tighten it
to specified torque.
Torque: 10 N ･
･･
･
m (1.0 kgf ･
･･
･
m/87 lb ･
･･
･
in)
12. Install relief valve and spring.
13. Install connector with a new O-ring. Be sure to discard used O-ring. Tighten the connector to
specified torque.
Torque: 59 N ･
･･
･
m (6.0 kgf ･
･･
･
m/43 lb ･
･･
･
ft)

Main Data and Specifications
General Specifications
Oil pump Type Vane
Operating fluid
ATF DEXRON®―III


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