2004 ISUZU TF SERIES cooling

6B-4 ENGINE COOLING (6VE1 3.5L)
NOTE: Antifreeze solution + Water = Total cooling
system capacity.
Total Cooling System Capacity
M/T 12.3Lit (13.0Us qt)
A/T 12.2Lit (12.9Us qt)

See section 0B MAINTENACE AND LUBRICATION.

Mixing ratio
NOTE: To maintain the corrosion resistance of the
aluminum radiator, water and antifreeze must be
combined in a 1:1 solution (50% antifreeze and 50%
water).



RTW46BSH000201

ENGINE COOLING (6VE1 3.5L) 6B-5
Diagnosis
Engine Cooling Trouble
Symptom Possible Cause Action
Engine overheating Low Engine Coolant level Replenish
Thermo meter unit faulty Replace
Faulty thermostat Replace
Faulty Engine Coolant temperature
sensor Repair or replace
Clogged radiator Clean or replace
Faulty radiator cap Replace
Low engine oil level or use of
improper engine oil Replenish or change oil
Clogged exhaust system Clean exhaust system or replace
faulty parts
Faulty Throttle Position sensor Replace throttle valve assembly
Open or shorted Throttle Position
sensor circuit Repair or replace
Damaged cylinder head gasket Replace
Engine overcooling Faulty thermostat Replace
Engine slow to warm–up Faulty thermostat Replace
Thermo unit faulty Replace

6B-6 ENGINE COOLING (6VE1 3.5L)
Draining and Refilling Cooling
System
Before draining the cooling system, inspect the system
and perform any necessary service to ensure that it is
clean, does not leak and is in proper working order.
The engine coolant (EC) level should be between the
“ MIN" and “MAX" lines of reserve tank when the engine
is cold. If low, check for leakage and add EC up to the
“ MAX" line.
There should not be any excessive deposit of rust o
r
scales around the radiator cap or radiator filler hole, and
the EC should also be free from oil.
Replace the EC if excessively dirty.
1. Completely drain the cooling system by opening the
drain plug at the bottom of the radiator.




P1010064
2. Remove the radiator cap.
WARNING: To avoid the danger of being burned, do
not remove the cap while the engine and radiato
r
are still hot. Scalding fluid and steam can be blown
out under pressure.
3. Disconnect all hoses from the EC reserve tank.
Scrub and clean the inside of the reserve tank with
soap and water. Flush it well with clean water, then
drain it. Install the reserve tank and hoses.
4. Refill the cooling system with the EC using a
solution that is 50 percent antifreeze.
Procedure for filling with coolant (in case of full change)
 Make sure that the engine is cool.
 Open radiator cap pour coolant up to filler neck.
 Pour coolant into reservoir tank up to “MAX" line.

 Tighten radiator cap and start the engine. Afte
r
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
not 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.

After tightening radiator cap, warm up the engine at
about 2000 rpm. Set heater adjustment to the
highest temperature position, and let the coolan
t
circulate also into heater water system.
 Check to see the thermostat has opened through
the needle position of water thermometer, conduct a
5 –minute idling again and stop the engine.
 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
cooling system and reservoir tank hose for leakage.
 Pour coolant into the reservoir tank up to “MAX"
line.

ENGINE COOLING (6VE1 3.5L) 6B-7
Water Pump
Water Pump and Associated Parts



030RS002
Legend
(1) Timing Belt (3) Water Pump Assembly
(2) Idle Pulley (4) Gasket


Removal
1. Disconnect battery ground cable.
2. Drain coolant.
3. Radiator hose (on inlet pipe side).
4. Remove timing belt. Refer to “Timing Belt" in this
manual.
5. Remove Idle pulley.
6. Remove water pump assembly.
7. Remove gasket.
Inspection
Make necessary repair and 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:
 Crack in the water pump body
 EC leakage from the seal unit
 Play or abnormal noise in the bearing
 Cracks or corrosion in the impeller.

Installation
1. Install gasket, clean the mating surface of gasket
before installation.
2. Install water pump assembly and tighten bolts to the
specified torque.
Torque: 25 N




m (2.5 kg




m/18 lb ft)
 Tightening order
The tightening order are in the illustrate.

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.