cooling ISUZU TF SERIES 2004 Repair Manual

6B-8 ENGINE COOLING (6VE1 3.5L)
NOTE: To prevent the oil leakage, apply the LOCTITE
262 or an equivalent, to the arrow marked fixing bol
t
thread.


030RW008
3. Idle pulley
 Install idle pulley and tighten bolt to the specified
torque.
Torque: 52 N




m (5.3 kg




m/38 lb ft)
4. Timing belt
 Install timing belt. Refer to timing belt installation
step in “Timing Belt" in this manual.
5. Connect radiator inlet hose and replenish EC.
6. Connect battery ground cable.

ENGINE COOLING (6VE1 3.5L) 6B-9
Thermostat
Thermostat and Associated Parts


031RW001

Legend
(1) Thermostat Housing
(2) Thermostat
(3) Outlet Pipe

Removal
1. Disconnect battery ground cable.
2. Drain engine coolant from the radiator and engine.
3. Disconnect radiator hose from the inlet pipe.
4. Remove thermostat housing.
5. Remove thermostat(2).
Inspection
Suspend the thermostat in a water–filled container
using thin wire. Place a thermometer next to the
thermostat.
Do not directly heat the thermostat.
Gradually increase the water temperature. Stir the wate
r
so that the entire water is same temperature.





031RS003
Confirm the temperature when the valve first begins to
open.
Valve opening temperature 74.5
 C 
  78.5
 C
(166.1
 F 
  173.3
 F)
Confirm the temperature when the valve is fully opened.
Valve full open temperature and lift More than
8.5mm (0.33 in) at 90
 C (194
 F)
Make necessary repair and parts replacement i
f
extreme wear or damage is found during inspection.
Installation
1. Install thermostat into the outlet pipe(4) making sure
that the air hole is in the up position.
2. Install thermostat housing and tighten bolts to the
specified torque.
Torque: 25 N




m (2.5 kg




m/18 lb ft)
3. Installation rubber hose.
4. Replenish engine coolant (EC).
5. Start engine and check for EC leakage.

6B-10 ENGINE COOLING (6VE1 3.5L)
Radiator
Radiator and Associated Parts



RTW36BLF000101
Legend (5) Bracket
(1) Radiator Hose (6) Reserve Tank Hose
(2) Drain Plug (7) Reserve Tank
(3) Fan Guide, Lower (8) Radiator Cap
(4) Fan Guide (9) Radiator Assembly

ENGINE COOLING (6VE1 3.5L) 6B-11
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.





P1010064
5. Remove fan guide(1), clips(2) on both sides and
the bottom lock, then remove lower fan guide(3)
with fan shroud(4).







RTW46BSH000101
6. Disconnect the reserve tank hose(6) from radiator.
7. Remove bracket(5).





110RW004
8. Lift up and remove the radiator assembly with
hose, taking care not to damage the radiator core
with a fan blade.
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 cente
r
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.

6B-12 ENGINE COOLING (6VE1 3.5L)
Valve opening vacuum kPa (psi) 1.96




4.91 (0.28





0.71)


110RS006
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
 Check the rubber hoses for swelling.

Cap tester: 5–8840–0277–0
Adapter: 5–8840–2603–0


110RS005
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.

ENGINE COOLING (6VE1 3.5L) 6B-13
6. Connect oil cooler hose to automatic transmission.




RTW36BSH000101
7. Connect battery ground cable.
8. Pour engine coolant up to filler neck of radiator, and
up to MAX mark of reserve tank.




RTW36BSH000101
Important operation (in case of 100% engine
coolant change) procedure for filling with engine
coolant.

Engine coolant change
1. To change engine coolant, make sure that the
engine is cool.
WARNING: When the coolant is heated to a high
temperature, be sure not to loosen or remove the
radiator cap. Otherwise you might get scalded by
hot vapor or boiling water. To open the radiato
r
cap, put a piece of thick cloth on the cap and
loosen the cap slowly to reduce the pressure when
the coolant has become cooler.
2. Open radiator cap and drain the cooling system by
loosening the drain valve on the radiator and on the
cylinder body.
NOTE: For best result it is suggested that the engine
cooling system be flushed at least once a year. It is
advisable to flash the interior of the cooling system
including the radiator before using anti-freeze
(ethylene-glycol based).
Replace damaged rubber hoses as the engine
anti-freeze coolant is liable to leak out even mino
r
cracks.
Isuzu recommends to use Isuzu genuine anti-freeze
(ethylen-glycol based) or equivalent, for the cooling
system and not add any inhibitors or additives.
CAUTION: A failure to correctly fill the engine
cooling system in changing or topping up coolant
may sometimes cause the coolant to overflow from
the filler neck even before the engine and radiato
r
are completely full.
If the engine runs under this condition, shortage o
f
coolant may possibly result in engine overheating.
To avoid such trouble, the following precautions
should be taken in filling the system.
3. To refill engine coolant, pour coolant up to filler neck
using a filling hose which is smaller in outside
diameter of the filler neck. Otherwise air between
the filler neck and the filling hose will block entry,
preventing the system from completely filling up.
4. Keep a filling rate of 9 liter/min. or less. Filling ove
r
this maximum rate may force air inside the engine
and radiator.
And also, the coolant overflow will increase, making
it difficult to determine whether or not the system is
completely full.
5.
After filling the system to the full, pull out the filling
hose and check to see if air trapped in the system is
disclodged and the coolant level goes down. Should
the coolant level go down, repeat topping-up until
there is no more drop in the coolant level.

6B-14 ENGINE COOLING (6VE1 3.5L)
6. After directly filling the radiator, fill the reservoir to
the maximum level.
7. Install and tighten radiator cap and start the engine.
After idling for 2 to 3 minutes, stop the engine and
reopen radiator cap. If the water level is lower,
replenish.
WARNING: When the coolant is heated to a high
temperature, be sure not to loosen or remove the
radiator cap. Otherwise you might get scalded by
hot vapor or boiling water. To open the radiato
r
cap, put a piece of thick cloth on the cap and
loosen the cap slowly to reduce the pressure when
the coolant has become cooler.
8.
After tightening radiator cap, warm up the engine at
about 2,000 rpm.
Set heater adjustment to the highest temperature
position, and let the coolant circulate also into
heater water system.
9. Check to see the thermostat has opened through
the needle position of water thermometer, conduct a
5-minute idling again and stop the engine.
10. When the engine has been cooled, check filler neck
for water level and replenish if required. Should
extreme shortage of coolant is found, check the
coolant system and reservoir tank hose for leakage.
11. Fill the coolant into the reservoir tank up to “MAX"
line.

ENGINE COOLING (6VE1 3.5L) 6B-15
Drive Belt and Cooling Fan
Drive Belt and Associated Parts



015RW005
Legend (4) Water Pump and Cooling Fan Pulley
(1) Crankshaft Pulley (5) Idle Pulley
(2) Generator (6) Tension Pulley
(3) Power Steering Pump (7) Drive Belt


The drive belt adjustment is not required as automatic
drive belt tensioner is equipped.
Inspection
Check drive belt for wear or damage, and replace with a
new one as necessary.
Installation
Install cooling fan assembly and tighten bolts/nuts to the
specified torque.
Torque : 25 N




m (2.5 kg




m/18 lb ft) for fan pulley
and fan bracket.
Torque : 10 N




m (1.0 kg




m/7 lb ft) for fan and
clutch assembly.
NOTE: Fan belts for 6VE1 Gasoline Engine mounted on
98MY (UX) have been brought into one. As a result, the
rotating direction of a fan belt is opposite to the direction
of cooling fan for 92 to 97MY 6VD1 with no
interchangeability.
Therefore, incorrect installation of a fan may cause the
air for cooling to flow in the opposite direction, this
resulting in the poor performance of the air-conditione
r
and a rise temperature in engine cooling water.

6B-16 ENGINE COOLING (6VE1 3.5L)
Main Data and Specifications
General Specifications

M/T A/T
Cooling system Engine coolant forced circulation
Radiator Tube type corrugated
Heat radiation capacity 81.4 kw (70.004 kcal/h)
Heat radiation area 9.42m
(0.875ft
)
Radiator front area 0.28m
(0.026ft
)
Radiator dry weight 5.0kg (11.0lb) 5.2kg (11.4lb)
Radiator cap valve opening pressure 93.3
122.7kpa (13.5
17.8psi)
Engine coolant pump Centrifugal impeller type
Delivery 300 (317) or more
Pump speed 5000  50 rpm
Thermostat Wax pellet type with air hole
Valve opening temperature 74.5
78.5C (166.1
173.3F)
Engine coolant total capacity 12.3lit (13.0U.S qt) 12.2lit (12.9U.S qt)

ENGINE COOLING (6VE1 3.5L) 6B-17
Torque Specifications
N




m (kg




m/ lb ft)




E06RW041