ISUZU TF SERIES 2004 Workshop Manual

ENGINE COOLING 6B – 11
Inspection and Repair
The water pump is not disassembled type.
Make necessary parts replacement if extreme wear or
damage is found during inspection. Should any of the
following problems occur, the entire water pump assembly
must be replaced.

Cracks in the water pump body

Coolant leakage from the seal unit

Excessive radial play or abnormal noise in the fan center
when rotate by hand

Excessive thrust play in the fan center (Standard play: less
than 0.2mm)

Cracks or corrosion in the impeller





























Installation
1. Water Pump
1) Install the water pump with new gasket.
2) Tighten bolts and nuts to specified torque.
Water Pump Bolt/Nut Torque N·m(kg·m/lb ft)
20 (2.0/14)

2. Fan Drive Belt and Pulley
1) Install the fan drive belt and fan pulley.
2) Apply tension to the fan drive belt by moving the
generator.
3) Apply a force of 98N(10kg/22 lb) to the drive belt mid-
portion to check the drive belt deflection.
Fan Drive Belt Deflection mm (in)
New belt: 4-7(0.16-0.28)
Reuse belt: 6-9(0.24-0.35)
030R300002


030R300001














3. Fan and Fan Clutch
1) Install the fan and fan clutch to pulley.
2) Tighten the nuts to specified torque.
Fan Clutch Nut Torque N·m(kg·m/lb in)
8(0.8/69)

4. Upper Fan Shroud

6B – 12 ENGINE COOLING



031R300003
5. Thermostat
Install the thermostat to the thermostat housing.
6. Water Outlet Pipe
1) Install the water outlet pipe with new gasket to the thermostat housing.
2) Tighten the outlet pipe bolt to specified torque.
Outlet Pipe Bolt Torque N ·m(kg ·m/lb ft)
19(1.9/14)

3) Connect the turbocharger-cooling pipe to outlet pipe.
7. Radiator Upper Hose
1) Connect the radiator upper hose to the water outlet pipe.
2) The knob of clamp shall be dircted to holizonal side.
3) Replenish the engine coolant.

ENGINE COOLING 6B – 13
THERMOSTAT
REMOVAL AND INSTALLATION
Read this Section carefully before performing any removal and installation procedure. This Section gives you
important points as well as the order of operation. Be sure that you understand everything in this Section before you
begin.

Removal
1. Radiator Upper Hose
1) Partially drain the engine coolant.
2) Remove the radiator upper hose.


2. Water Outlet Pipe 3) Disconnect the turbocharger-cooling pipe from outlet pipe.
4) Loosen the fixing bolt and remove the water outlet bolt.
3. Thermostat
Remove the thermostat from the thermostat housing.
Take care not to damage the thermostat.

031R300003

Inspection and Repair
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is discovered
during inspection.


031RY00005
Operating Test of Thermostat
1. Completely submerge the thermostat in water.
2. Heat the water. Stir the water constantly to avoid direct heat being
applied to the thermostat.
3. Check the thermostat initial opening temperature.
Thermostat Initial Opening Temperature
C (
F)
82 (180)

4. Check the thermostat full opening temperature.
Thermostat Full Opening Temperature
C (
F)
95 (203)

Valve Lift At Fully Open Position mm (in)
9.5 (0.37)

6B – 14 ENGINE COOLING

Thermometer
 Agitating rod
 Wooden piece
















Installation
1. Thermostat
Install the thermostat to the thermostat housing.
2. Water Outlet Pipe
3) Install the water outlet pipe with new gasket to the thermostat housing.
4) Tighten the outlet pipe bolt to specified torque.
Outlet Pipe Bolt Torque N ·m(kg ·m/lb ft)
19(1.9/14)

5) Connect the turbocharger-cooling pipe to outlet pipe.
031R300003


3. Radiator Upper Hose
1) Connect the radiator upper hose to the water outlet pipe.
2) The knob of clamp shall be directed to holizonal side.
3) Replenish the engine coolant.

ENGINE COOLING 6B – 15
RADIATOR
REMOVAL AND INSTALLATION
Radiator and Associated Parts




RTW36BLF000101
Legend
1. Radiator Hose
2. Drain Plug
3. Fan Guide, Lower
4. Fan Guide
5. Bracket


6. Reserve Tank Hose
7. Reserve Tank
8. Radiator Cap
9. Radiator Assembly

6B – 16 ENGINE COOLING

P1010064
Removal
1. Disconnect battery ground cable.
2. Loosen a drain plug to drain EC.
3. Disconnect oil cooler hose on automatic transmission (A/T).
4. Disconnect radiator inlet hose and outlet hose from the engine.





PTW46BSH000101
5. Remove fan guide(1), clips(2) on both sides and the bottom
lock, then remove lower fan guide(3) with fan shroud(4).
6. Disconnect the reserve tank hose(6) from radiator.





RTW36BMH000101
7. Remove bracket(5).

8. Lift up and remove the radiator assembly with hose, taking
care not to damage the radiator core with a fan blade.

ENGINE COOLING 6B – 17
Inspection and Repair
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is discovered
during inspection.


Radiator Cap
Measure the valve opening pressure of the pressurizing valve
with a radiator filler cap tester.
Replace the cap if the valve opening pressure is outside the
standard range.
Valve opening pressure kPa (psi) 93.3





122.7 (13.5





17.8)
Cap tester: 5–8840–0277–0
Adapter: 5–8840–2603–0
Check the condition of the vacuum valve in the center of the
valve seat side of the cap. If considerable rust or dirt is found,
or if the valve seat cannot be moved by hand, clean or replace
the cap.





110RS006

Valve opening vacuum kPa (psi) 1.96




4.91 (0.28




0.71)


Radiator Core
1. A bent fin may result in reduced ventilation and overheating
may occur. All bent fins must be straightened. Pay close
attention to the base of the fin when it is being straightened.
2. Remove all dust, bugs and other foreign material.

Flushing the Radiator
Thoroughly wash the inside of the radiator and the engine
coolant passages with cold water and mild detergent. Remove
all signs of scale and rust.

Cooling System Leakage Check
Use a radiator cap tester to force air into the radiator through
the filler neck at the specified pressure of 196 kPa (28.5 psi)
with a cap tester:
 Leakage from the radiator
 Leakage from the coolant pump
 Leakage from the water hoses

6B – 18 ENGINE COOLING




110RS005

 Check the rubber hoses for swelling.

Installation
1. Install radiator assembly (9) with hose, taking care not to
damage the radiator core with a fan blade.
2. Support the radiator upper tank with the bracket (5) and
secure the radiator.
3. Connect reserve tank hose (6).
4. Install lower fan guide (3).
5. Connect radiator inlet hose and outlet hose (1) to the
engine.





RTW36BMH000101

6. Connect oil cooler hose to automatic transmission.
7. Connect battery ground cable.

ENGINE COOLING 6B – 19




RTW36BSH000101

8. Pour engine coolant up to filler neck of radiator, and up to
MAX mark of reserve tank.

Important operation (in case of 100% engine coolant
change) procedure for filling with engine coolant.


Engine coolant change
Refer to 6B-8 (Draining and Refilling Cooling System).

6B – 20 ENGINE COOLING
FAN CLUTCH WITH COOLING FAN
INSPECTION AND REPAIR
Make necessary correction or parts replacement if wear, damage or any other abnormal condition are found through
inspection.


033R300001
Visually inspect for damage, leak (sillicon grease) or other
abnormal conditions.
1. Inspection (on-vehicle)
1) Turn the fan clutch by hand when in a low temperature
condition before starting the engine, and confirm that it
can be turned readily.
2) Start the engine to warm it up until the temperature at
the fan clutch portion gets to around 80
C. Then stop
the engine and confirm that the fan clutch can be
turned with considerable effort (clutch torque) when
turned by hand.
If the fan clutch rotates more readily, however, this
indicates that the silicone grease is leaking internally.
Replace the fan clutch with a new one.



033RY00011
2. Inspection (in unit)
Warm up the bimetal of the fan clutch by using the heat
gun until the temperature gets to about 80
C when
measured with the thermistor. Then confirm that the fan
clutch can be turned with considerable effort (clutch
torque).
If the fan clutch retates more readily at this time, this
indicates that the silicone grease is leaking internally.
Replace the fan clutch with a new one.