engine coolant ISUZU KB P190 2007 Workshop Repair Manual

Engine Cooling – V6 Engine Page 6B1–25

3.4 Cleaning Cooling System
NOTE
• Before carrying out reverse flushing
procedures, it is recommended that a
cleaning solution be used to loosen scale and
corrosion. Only use a Holden approved
radiator cleaner following the instructions on
the container label.
• This operation should only be carried out
when the engine and radiator are at ambient
temperature.
• When using specialised cooling system
flushing equipment, connect the equipment as
recommended by the manufacturer.
Cooling System Reverse Flush
Radiator

Refer to ‘
‘‘
‘
Environmental Issues ’
’’
’
in 3.1
Service Notes, before draining the coolant.
1 Drain the cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.

Always wear eye protection when working
with spring-type hose clamps. Failure to do
so may result in eye injury.
2 Remove the lower radiator outlet hose (1) at the coolant inlet pipe connection (2).
3 Remove the upper radiator inlet hose (3) at the coolant outlet housing connection (4).
4 Attach a lead-away hose to the open end of the upper radiator hose.
5 Attach a suitable piece of hose or adaptor between the flushing gun and the open end of the lower
radiator hose.
6 Connect and operate the flushing equipment as recommended by the manufacturer.

Apply air pressure gradually and not in
excess of 120 kPa, otherwise radiator
damage will result.
Figure 6B1 – 22
7 Continue flushing until the water from the lead-away hose runs clean and clear.
8 Install all disconnected hoses, ensuring that they are correctly positioned and securely clamped.
9 Fill the cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.

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ISUZU KB P190 2007

Engine Cooling – V6 Engine Page 6B1–26

10 Pressure test the cooling system. Refer to 3.7 Pressure Testing in this Section.
Engine

Refer to ‘
‘‘
‘
Environmental Issues ’
’’
’
in 3.1
Service Notes, before draining the coolant.
1 Drain the cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.

Always wear eye protection when working
with spring-type hose clamps. Failure to do
so may result in eye injury.
2 Remove the upper and lower radiator hoses from the coolant outlet housing and coolant inlet pipe connections. Refer to Figure 6B1 – 22.
3 Remove the thermostat housing from the rear of the engine block. Refer to 6A1 Engine Mechanical – V6..
4 Remove the thermostat from the thermostat housing and reinstall the housing to the rear of the intake manifold. Refer to 3.8 Thermostat in this Section.
5 Remove both heater hoses (1) and (2) from their connections at the heater pipe assembly, noting
which hose was connected to which connection.
Seal the heater pipe assembly connections by
looping the heater inlet connection to the outlet
connection using a suitable piece of hose and two
hose clamps.
6 Install a lead-away hose to the coolant inlet pipe connection and a length of suitable hose between
the coolant outlet housing connection and the
flushing equipment.
7 Connect and operate the flushing equipment as recommended by the manufacturer.
Figure 6B1 – 23
8 Continue flushing until the water from the lead-away hose runs clear.
9 Remove the coolant recovery reservoir, flush it out with clean water and install. Refer to 3.9 Coolant Recovery Reservoir in this Section.
10 Install the thermostat. Refer to 3.8 Thermostat in this Section.
11 Install all disconnected hoses, ensuring that they are correctly positioned and securely clamped.
12 Fill the cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.
13 Pressure-test the cooling system. Refer to 3.7 Pressure Testing in this Section.

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Engine Cooling – V6 Engine Page 6B1–27

Heater Hoses and Core

Refer to ‘
‘‘
‘
Environmental Issues ’
’’
’
in 3.1
Service Notes, before draining the coolant.
1 Drain the cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.

Always wear eye protection when working
with spring-type hose clamps. Failure to do
so may result in eye injury.
2 Remove both heater hoses (1) and (2) from their connections at the heater pipe assembly, noting
which hose was connected to which connection.
3 Direct the hose (1) that was connected to the heater pipe assembly’s front connection into a
suitable container.
4 Attach the hose (2) from the rear-most connection to the flushing gun.
5 Cycle the heater switch to ensure that the water valve is open.


Figure 6B1 – 24
6 Connect and operate the flushing equipment as recommended by the manufacturer.

Apply air pressure gradually and not in
excess of 130 kPa, otherwise heater core
damage will result.
7 Install all disconnected hoses, ensuring that they are correctly positioned and securely clamped.
8 Fill the cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.
9 Pressure test the cooling system. Refer to 3.7 Pressure Testing in this Section.

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Engine Cooling – V6 Engine Page 6B1–29

Inspect
The four views in Figure 6B1 – 26 show the various stages of drive belt wear, to assist in belt replacement decisions.
NOTE
Condition of the belt ribs can be better assessed
if the belt is wrapped over the coolant pump drive
pulley.

Figure 6B1 – 26
Legend
A New Belt: No cracks or c hunks.
B Moderately Used Belt: Few cra cks, with some wear on the ribs and in the grooves. Belt replacement not required.
C Severely Used Belt: Several cracks per 30 mm. S hould be replaced before chunking occurs
D Failed Belt: Separation of rib material from backing (chunking). Belt must be replaced immediately.

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Engine Cooling – V6 Engine Page 6B1–30

3.6 Coolant Hoses

Always wear protective safety glasses when
working with spring type hose clamps. Failure
to do so could result in eye injury.
Coolant hoses are installed as shown in the following illustrations, taking note that there are a number of variants,
depending on a specific vehicle specification.
Hose connections should be thoroughly cleaned before installing any new hose.
After all hoses are installed, always refill the cooling system with correct concentration of coolant, refer to 3.3 Draining
and Filling Cooling System and pressure test cooling system, refer to 3.7 Pressure Testing in this Section.

Figure 6B1 – 27
Legend
1 Radiator Hose – Upper
2 Radiator Hose – Lower
3 Hose Clamp – Upper Hose to Engine Outlet Housing 4 Hose Clamp – Upper Hose to Radiator Inlet
5 Hose Clamp – Lower Hose to Radiator Outlet
6 Hose Clamp – Lower Hose to Engine Coolant Inlet Pipe

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Engine Cooling – V6 Engine Page 6B1–31

3.7 Pressure Testing
Coolant Filler Cap Pressure Testing

Refer to 3.1 Service Notes in this Section, for
important safety items.




1 Allow engine to cool to ambient temperature (less than 50 ° C), then remove coolant filler cap.
2 Inspect and clean both sides (1) of coolant filler cap gasket with a wet cloth.
NOTE
Use only water to wet the cleaning cloth.
Figure 6B1 – 28
3 Lift centre vacuum valve. Clean and inspect the gasket and sealing surface under the valve (1).
Figure 6B1 – 29

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Engine Cooling – V6 Engine Page 6B1–32

4 Attach coolant filler cap (2) to a commercially
available cooling system pressure tester (1), using
the pressure cap adaptor.
5 Slowly pressurise cap to 120 – 130 kPa. The cap is serviceable if it unloads slightly above this pressure
range and holds pressure at 120 kPa.
NOTE
Should the cap fail to reach or hold the
specified pressure, replace the cap.

Figure 6B1 – 30
6 Prior to installing coolant filler cap ensure that the coolant filler neck cap seating surface is clean and
free from obstruction.
Figure 6B1 – 31
Cooling System Pressure Testing

Refer to 3.1 Service Notes in this Section, for
important safety items.
1 Allow the engine to cool to ambient temperature (less than 50 ° C), then remove coolant filler cap.
2 Ensure that the coolant level is correct.

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Engine Cooling – V6 Engine Page 6B1–33

3 Install the coolant filler neck adaptor, to a
commercially available cooling system pressure tester
(1).
4 Install the assembly to the engine coolant filler neck.
5 Using compressed air, blow dry any spilled coolant around coolant filler neck.

Do not exceed the stated pressure, as
damage to the cooling system could
otherwise result.
6 Using the cooling system pressure tester pump, pressurise cooling system to 130 kPa absolute
maximum and check for leaks at the following points:
• All hoses and hose connections
• Overflow hose connection at coolant outlet
housing connection

Figure 6B1 –
––
–
32
• Radiator seams and core
• Corroded or faulty engine W elch plugs
• Coolant pump and gasket
• Thermostat housing and coolant inlet pipe connection
• Radiator drain tap and bleed screw
• Vehicle heating system (e.g. heater core and water valve)
NOTE
For heater Removal and Installation, refer to 2A –
Heater and Air-conditioning.
7 Check engine oil dipstick for evidence of engine oil contamination with coolant.
8 If pressure will not hold, there is a leak in the cooling system. Repair as necessary.
NOTE
If visible loss of coolant is not evident from
pressure testing, then the use of a dye and black
light, may be necessary. Refer to 4.7 Black
Light and Dye Leak Diagnosis Method, in this
Section.

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Engine Cooling – V6 Engine Page 6B1–34

3.8 Thermostat
Remove

Do not remove coolant filler cap while the
engine coolant temperature is above 50 °
°°
°
C, as
personal injury may result.
1 Allow engine to cool to ambient temperature (less than 50 ° C), then remove the coolant filler cap (located at the
front left-hand side of the engine).

Disconnection of the battery affects certain
vehicle electronic systems. Refer to 00
Warnings, Cautions and Notes, before
removing the ground lead.
2 Disconnect the battery ground lead. Refer to 6D1-3 Battery – V6.


Refer to ‘
‘‘
‘
Environmental Issues ’
’’
’
in 3.1
Service Notes, before draining the coolant.
3 Drain the coolant from the system. Refer to 3.3 Draining and Filling Cooling System in this Section.
4 Remove the complete intake manifold assembly. Refer to 6A1 Engine Mechanical – V6.
5 Plug each of the exposed intake ports with lint free cloth to prevent the entry of foreign matter.
6 Remove the coolant inlet pipe. Refer to 3.12 Coolant Inlet Pipe in this Section.


Always wear protective safety glasses when
working with spring type hose clamps.
Failure to do so could result in eye injury.
7 Use a straight-blade screwdriver (3) to release the heater hose quick connect clips (4).
8 Disconnect the heater hoses (1) from the heater pipes (2) in two places.
Figure 6B1 –
––
–
33

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Engine Cooling – V6 Engine Page 6B1–35

9 To gain easier access to the heater pipe flange and
thermostat housing bolts, disconnect the engine
harness and lay back on the right side of the engine
bay. Apart from those harness connectors removed
during the intake manifold removal, this involves the
removal of wiring harness connectors and fasteners,
as detailed:
a Pull out the release bar (arrows) on each of the ignition coil packs (1) on cylinders 2, 4 and 6,
before disconnecting each connector.
b The coolant temperature sensor.
c The left side Pre-O2 sensor connector, 2, 4 & 6.
NOTE
Refer to 8A – Electrical Body & Chassis for the
location of harness connectors, not shown.

Figure 6B1 –
––
–
34
10 Remove the bolt (1) securing the engine harness ground terminal (2), to the cylinder block.
11 Prise both locking legs of the left side engine harness former (4), free, then lift up on the harness former to
release.

Figure 6B1 –
––
–
35
12 W orking at the rear of the engine, disconnect the engine harness to transmission harness connector (1),
as required.
13 Remove the two bolts (2) securing the engine harness former (3) to the rear of the engine.
14 Carefully lift the engine harness free and drape on the right side of the engine.


NOTE
For further information on removing the
thermostat housing and associated components,
refer to 6A1 Engine Mechanical – V6.
Figure 6B1 –
––
–
36

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