belt ISUZU TF SERIES 2004 Workshop Manual

HEATER AND AIR CONDITIONING 1-83

AIR CONDITIONING CYCLE TROUBLESHOOTING

TROUBLE POSSIBLE CAUSE CORRECTION
No cooling or
insufficient
cooling
1. Magnetic clutch does not run


Refer to “MAGNETIC CLUTCH”
troubleshooting in this section
2. Compressor is not rotating properly

Drive belt loosened or broken

Adjust the drive belt to the specified
tension or replace the drive belt


Magnetic clutch face is not clean and
slips
Clean the magnetic clutch face or replace




Incorrect clearance between magnetic
drive plate and pulley

Adjust the clearance (Refer to
“COMPRESSOR OVERHAUL”



Compressor oil leaks from shaft seal or
shell

Replace the compressor




Compressor seized

Replace the compressor

3. Insufficient or excessive charge of
refrigerant

Discharge and recover refrigerant.
Recharge to specified amount.
4. Leaks in the refrigerant system




Check refrigerant system for leaks and
repair as necessary
Discharge and recover refrigerant.
Recharge to specified amount.
5. Condenser clogged or insufficient radiation


Clean the condenser or replace as
necessary


Check radiator or condenser fan function

6. Temperature control link unit of the heater
unit defective

Repair the link unit

7. Unsteady operation due to foreign
substance in expansion valve

Replace the expansion valve

8. Poor operation of electronic thermostat


Check electronic thermostat and replace
as necessary
Insufficient
velocity
of cooling air

1. Evaporator clogged or frosted


Check evaporator core and replace or
clean the core
2. Air leaking from cooling unit or air duct

Check evaporator and duct connection,
then repair as necessary

3. Blower motor does not rotate prop-erly


Refer to “FAN CONTROL KNOB (FAN
SWITCH)” troubleshooting in this section

* For the execution of the charging and discharging operation in the table above, refer to the “RECOVERY,
RECYCLING, EVACUATING AND CHARGING” in this section.

POWER-ASSISTED STEERING SYSTEM 3B-7


Power Steering System Test
Test Procedure
F02RX002
Legend
(1) Bolt
(2) Hose
(3) Power Steering Unit
(4) Power Steering Pump


Test of fluid pressure in the power steering system is
performed to determine whether or not the oil pump and
power steering unit are functioning normally.
The power steering system test is used to identify and
isolate hydraulic circuit difficulties. Prior to performing
this test, the following inspections and corrections, i
f
necessary, must be made.


Inspect pump reservoir for proper fluid level.


Inspect pump belt for proper tension.


Inspect pump driver pulley condition.
1. Place a container under the pump to catch the fluid
when disconnecting or connecting the hoses.
2.
With the engine NOT running, disconnect the
pressure hose at the power steering pump and
install power steering tester 5-8840-0135-0 as
shown in the illustration. The gage must be between
the shutoff valve and pump. Open the shutoff valve.
3. Check the fluid level. Fill the reservoir with powe
r
steering fluid, to the "Full" mark. Start the engine,
then turn the steering wheel and momentarily hold it
against a stop (right or left). Turn the engine off and
check the connections at tester for leakage.
4. Bleed the system. Refer to Bleeding the Powe
r
Steering System in this section.
5. Start the engine and check the fluid level. Add
power steering fluid if required. When the engine is
at normal operating temperature, increase engine
speed to 1500 rpm.
CAUTION: Do not leave shutoff valve fully closed
for more than 5 seconds, as the pump could
become damaged internally.

3B-8 POWER-ASSISTED STEERING SYSTEM

6. Fully close the shutoff valve. Record the highest
pressures.


If the pressure recorded is within 9300-9800 kPa
(95-100 kg/cm
2/1350-1420 psi), the pump is
functioning within its specifications.


If the pressure recorded is higher than 9800 kPa
(100 kg/cm
2/1420 psi), the valve in the pump is
defective.


If the pressure recorded is lower than 9300 kPa (95
kg/cm
2/1350 psi), the valve or the rotating group in
the pump is defective.
7. If the pump pressures are within specifications,
leave the valve open and turn (or have someone
else turn) the steering wheel fully in both directions.
Record the highest pressures and compare with the
maximum pump pressure recorded in step 6. If this
pressure cannot be built in either side of the powe
r
steering unit, the power steering unit is leaking
internally and must be replaced.
8. Shut the engine off, remove the testing gauge.
9. Reconnect the pressure hose, check the fluid level
and make the needed repairs.
10. If the problem still exists, the steering and fron
t
suspension must be thoroughly examined.

Maintenance
The hydraulic system should be kept clean and fluid
level in the reservoir should be checked at regula
r
intervals and fluid added when required. Refer to
Recommended Fluids and Lubricants in General
Information section for the type of fluid to be used and
the intervals for filling.
If the system contains some dirt, flush it as described in
this section. If it is exceptionally dirty, the pump must be
completely disassembled before further usage. (The
steering unit cannot be disassembled.)
All tubes, hoses, and fittings should be inspected for
leakage at regular intervals. Fittings must be tight. Make
sure the clips, clamps and supporting tubes and hoses
are in place and properly secured.
Power steering hoses and lines must not be twisted,
kinked or tightly bent. Air in the system will cause
spongy action and noisy operation. When a hose is
disconnected or when fluid is lost, for any reason, the
system must be bled after refilling. Refer to Bleeding the
Power Steering System in this section.


Inspect belt for tightness.


Inspect pulley for looseness or damage. The pulle
y
should not wobble with the engine running.


Inspect hoses so they are not touching any othe
r
parts of the vehicle.


Inspect fluid level and fill to the proper level.

Fluid Level
1. Run the engine until the power steering fluid
reaches normal operating temperature, about 55
C (130
F), then shut the engine off.
2. Check the level of fluid in the reservoir.
3. If the fluid level is low, add power steering fluid as
specified in General Information to the proper level
and install the receiver cap.
4. When checking the fluid level after the steering
system has been serviced, air must be bled from
the system. Refer to Bleeding the Power Steering
System in this section.

Bleeding The Power Steering System
When a power steering pump or unit has been installed,
or an oil line has been disconnected, the air that has
entered the system must be bled out before the vehicle
is operated. If air is allowed to remain in the powe
r
steering fluid system, noisy and unsatisfactory operation
of the system may result.

Bleeding Procedure
When bleeding the system, and any time fluid is added
to the power steering system, be sure to use only powe
r
steering fluid as specified in General Information.
1. Fill the pump fluid reservoir to the proper level and
let the fluid settle for at least two minutes.
2. Start the engine and let it run for a few seconds. Do
not turn the steering wheel. Then turn the engine
off.
3. Add fluid if necessary.
4. Repeat the above procedure until the fluid level
remains constant after running the engine.
5. Raise and support the front end of the vehicle so
that the wheels are off the ground.
6. Start the engine. Slowly turn the steering wheel right
and left, lightly contacting the wheel stops.
7. Add power steering fluid if necessary.
8. Lower the vehicle, set the steering wheel at the
straight forward position after turning it to its full
steer positions 2 or 3 times, and stop the engine.
9. Check the fluid level and refill as required.
10. If the fluid is extremely foamy, allow the vehicle to
set a few minutes, then repeat the above procedure.

Flushing The Power Steering System
1. Raise and support the front end of the vehicle off
the ground until the wheels are free to turn.
2. Remove the fluid return line at the pump inlet
connector and plug the connector port on the pump.
Position the line toward a large container to catch
the draining fluid.
3. While running the engine at idle, fill the reservoi
r
with new power steering fluid. Turn the steering
wheel in both directions. Do not contact or hold the
steering wheel to the wheel stops. This will cause
the pump to go to pressure relief mode, which ma
y
cause a sudden fluid overflow at the reservoir.

3B-16 POWER-ASSISTED STEERING SYSTEM

Power Steering Pump
Power Steering Pump and Associated Parts (4JH1-TC, 4JA1-TC, 4JA1-L)
442R300002
Legend
(1) Pump Assembly
(2) Hose, Suction
(3) Hose, Flexible
(4) Bolt


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: 34 - 46 N·m (3.5 – 4.7 kg·m/25 - 34 lb ft)
2. Install the flexible hose.
Tighten the eye bolt to specified torque.
Torque: 49 - 59 N·m (5.0 – 6.0 kg·m/36 - 43 lb ft)
3. Install the pulley and tighten the bolt to the specified
torque.
Torque: 26 - 30 N·m (2.7 –3.1 kg·m/20 - 22 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.

POWER-ASSISTED STEERING SYSTEM 3B-21

Power Steering Pump and Associated Parts (C24SE)
RTW33BLF000801

Legend
(1) Pump Assembly
(2) Hose, Suction
(3) Hose, Flexible

(4) Bolt
(5) Connector, Pressure switch

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. Disconnect the oil pressure switch connector.
7. 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: 34-46 N·m (3.5-4.7 kg·m/25-34 lb ft)
2. Connector the oil pressure switch connector.
3. Install the flexible hose.
Tighten the eye bolt to specified torque.
Torque: 49-59 N·m (5.0-6.0 kg·m/36-43 lb ft)
4. Install the pulley and tighten the bolt to the specified
torque.
Torque: 69-88 N·m (7.0-9.0 kg·m/51-65 lb ft)

5. Install the drive belt.
6. Connect the suction hose, then fill and bleed
system.
Refer to Bleeding the Power Steering System in this
section.

3B-26 POWER-ASSISTED STEERING SYSTEM

Power Steering Pump and Associated Parts (6VE1)
RTW33BLF000701

Legend
(1) Pump Assembly
(2) Hose, Suction
(3) Hose, Flexible


(4) Bolt
(5) Connector, Pressure switch

Removal
1. Remove the drive belt.
2. Place a drain pan below the pump.
3. Disconnect the suction hose.
4. Disconnect the flexible hose.
5. Disconnect the oil pressure switch connector.
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: 31-63 N·m (3.2-6.4 kg·m/23-46 lb ft)
2. Connector the oil pressure switch connector.
3. Install the flexible hose.
Tighten the eye bolt to specified torque.
Torque: 49 - 59 N·m (5.0 – 6.0 kg·m/36 - 43 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.