engine coolant ISUZU TF SERIES 2004 Manual PDF
Page 1874 of 4264
6A-50 ENGINE MECHANICAL (6VE1 3.5L)
012RS009
1. Install engine assembly. Tighten engine mount
fixing bolts to frame to the specified torque.
Torque: 41 N
m (4.2 kg
m/30 lb ft)
2. Reconnect fuel hose to fuel pipe on engine.
3. Install transmission assembly. Refer to
Transmission section in this manual.
4. Reconnect two heater hoses to engine.
5. Install flywheel dust covers.
6. Install exhaust pipe and temporally tighten two
(each bank) rear exhaust flange nuts then tighten
three stud nuts (each bank) between exhaus
t
manifold and exhaust pipe, finally tighten rear side
stud nuts to the specified torque.
Torque: 67 N
m (6.8 kg
m/49 lb ft)
LTW36FSH000101
7. Reconnect O2 sensor connector.
8. 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.
9. Install air conditioner compressor to engine and
tighten to the specified torque.
Torque : 43 N
m (4.4 kg
m/32 lb ft)
10. Install power steering pump, tighten fixing bolt to
the specified torque.
Torque :
M8 bolts : 25 N
m (2.5 kg
m/18 lb ft)
M10 bolts : 43 N
m (4.4 kg
m/32 lb ft)
11. Move drive belt tensioner to loose side using
wrench, then install drive belt to normal position.
850RW001
Legend
(1) Crankshaft Pulley
(2) Cooling Fan Pulley
(3) Tensioner
(4) Generator
(5) Air Conditioner Compressor
(6) Power Steering Oil Pump
(7) Drive Belt
12. Install upper fan shroud.
13. Reconnect radiator upper and lower hoses.
14. Reconnect coolant reserve tank hose to radiator.
15. Reconnect generator harness connector.
16. Reconnect starter harness connector.
17. Reconnect bonding cable terminal on left bank
18. Reconnect bonding cable terminal on the back o
f
right dash panel.
Page 1926 of 4264
6B-2 ENGINE COOLING (6VE1 3.5L)
General Description
030RW001
Legend (7)Cylinder Head
(1) Water Pump (8) Right Bank
(2) Thermostat (9) Throttle Body
(3) Radiator (10) Cylinder Block
(4) Reserve Tank (11) Cylinder Head
(5) Cooling Fan (12) Left Bank
(6) Cylinder Block (13) Heater
The engine cooling system consists of the radiator, the
water pump, the cooling fan, and the thermostat.
To quickly increase cold engine coolant temperature fo
r
smooth engine operation, the coolant is circulated by
the water pump and thermostat through the bypass
hose and back to the cylinder body.
The coolant does not circulate through the radiator.
When the coolant temperature reaches specified value,
the thermostat will begin to open and a gradually
increasing amount of coolant will circulate through the
radiator.
The thermostat will be fully open when the coolan
t
temperature reaches specified value. All of the coolant
is now circulating through the radiator for effective
engine cooling.
Page 1927 of 4264
ENGINE COOLING (6VE1 3.5L) 6B-3
Water Pump
The EC pump is a centrifugal impeller type and is driven
by a timing belt.
030RS001
Thermostat
The thermostat is a wax pellet type with a air hole(1)
and is installed in the thermostat housing.
031RW002
Radiator
The radiator is a tube type with corrugated fins. In order
to raise the boiling point of the coolant, the radiator is
fitted with a cap in which the valve is operated at 93.3
122.7 kPa (13.5 17.8 psi) pressure. (No oil cooler
provided for M/T)
110RS001
Antifreeze Solution
Calculating mixing ratio
F06RW005
Page 1929 of 4264
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
Page 1930 of 4264
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.
Page 1931 of 4264
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.
Page 1933 of 4264
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.
Page 1936 of 4264
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.
Page 1937 of 4264
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.
Page 1938 of 4264
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.