2007 ISUZU KB P190 ECU

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 6B1–35

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 –
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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 –
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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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Engine Cooling – V6 Engine Page 6B1–37

Test
1 W ith the thermostat (1) installed in the housing,
suspend it and a suitable thermometer (2) in a
container of 50% clean fresh water and 50% Dexron ®
long life coolant, (conforming to GM 6277M).
NOTE
Neither the thermostat assembly (1) nor the
thermometer (2) should rest on the bottom of the
container because of uneven concentration of
heat at this point when the container is heated.
2 Heat container until thermostat begins to open. Agitate solution to ensure uniform temperature. Note
temperature and ensure thermostat opens within
specified temperature range.
Thermostat Opening Specifications
Opening Temperature ........................................ 82 ° C
Fully Open Temperature .................................... 95 ° C
3 Replace thermostat if it does not meet these operating
conditions.
Figure 6B1 –
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39
Dismantle

Only dismantle the thermostat if a reverse
flushing operation of the cylinder block is to
be carried out. If the testing operation
indicates that the thermostat is faulty, then
the housing and thermostat are only serviced
as an assembly.
Remove thermostat (1) from thermostat housing (2) as
follows:
a Secure the thermostat housing by gripping in a vice fitted with soft jaws.

Always wear protective safety glasses when
working with spring-loaded devices. Failure
to do so could result in eye injury.
b Depress the retaining bar (3) on both sides of the thermostat and rotate the thermostat until it
clears the retaining lugs (4) on the thermostat
housing (2).
c Release the thermostat spring force.
d Remove the thermostat assembly from the thermostat housing.
Figure 6B1 – 40
Reassembly
The reassembly process is the reverse to that used for disassembly, with the following exceptions:
1 Check that the valve sealing surface is undamaged.
2 W ipe the valve sealing surface to ensure a clean surface.

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Engine Cooling – V6 Engine Page 6B1–38

Install

Always wear protective safety glasses when
working with spring-loaded devices. Failure to
do so could result in eye injury.
1 Install the thermostat into the housing (reverse to removal procedure).
2 Ensure that the engine block and thermostat housing mating surfaces are clean and dry.
3 Install a new gasket to the thermostat housing.
4 Install the thermostat housing to the engine block and secure with the attaching bolts (with rubber grommets installed). Tighten all bolts to the correct torque specification.
Thermostat housing to engine
block bolt torque specification ..............................10 N.m
5 Ensure that the heater pipe assembly and thermostat housing mating surfaces are clean and dry.
6 Install new O-rings to the heater pipe assembly.
7 Install heater pipe assembly to thermostat housing and secure with the attaching bolts. Tighten all bolts to the correct torque specification.
Heater pipe assembly to thermostat
housing bolt torque specification ..........................10 N.m
8 Install heater pipe assembly to right-hand cylinder head bolt. Tighten bolt to the correct torque specification. Heater pipe assembly to cylinder
head bolt torque specification ..............................35 N.m

Always wear protective safety glasses when
working with spring type hose clamps. Failure
to do so could result in eye injury.
9 Reinstall the engine wiring harness, securing the rear harness former to the rear of the engine with the two retaining bolts, tightened to the correct torque specification.
Rear engine harness former
retaining bolts torque specification .......................15 N.m
10 Reinstall the left side engine harness former to the two locating pegs, then push inward to secure.
11 Reinstall the bolt securing the engine harness ground terminal, to the left side of the cylinder block and tighten to the correct torque specification.
Engine harness ground terminal
attaching bolt torque specification ........................12 N.m
12 Reinstall each wiring harness connector to its correct location, ensuring that all security clips are installed correctly.
13 Connect the heater hoses to the heater pipe assembly.
14 Install the coolant inlet pipe. Refer to 3.12 Coolant Inlet Pipe in this Section.
15 Close the radiator drain tap on the lower LHS of the radiator and remove the piece of rubber tubing to the tap outlet.
16 Reinstall the complete intake manifold assembly. Refer to 6A1 Engine Mechanical.
17 Refill cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.

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Engine Cooling – V6 Engine Page 6B1–48

Install
1 Ensure that the coolant inlet pipe and thermostat housing mating surfaces are clean and dry.
2 Install new O-ring to the coolant inlet pipe.
3 Install coolant inlet pipe at the thermostat housing and secure with the attaching bolt. Tighten all bolts to the correct torque specification.
Coolant inlet pipe to thermostat
housing bolt torque specification ..........................23 N.m
4 Raise the front of the vehicle and support on safety stands. Refer to 0A General Information for the location of jacking and support points.
5 Reinstall the coolant inlet pipe to the engine block and secure with the bolt tightened to the correct torque specification.
Coolant inlet pipe to engine block bolt
torque specification .............................................25 N.m

Always wear protective safety glasses when
working with spring type hose clamps. Failure
to do so could result in eye injury.
6 Connect the lower radiator outlet hose and clamp to the coolant inlet pipe connection.
7 Close the radiator drain tap on the lower RHS of the radiator and remove the piece of rubber tubing to the tap outlet.
8 Lower the front of the vehicle.
9 Refill cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.
10 Check for coolant leaks. Refer to 3.7 Pressure Testing in this Section.
11 Reconnect battery ground lead. Refer to 8A – Electrical Body & Chassis.

3.13 Cooling Fan and Shroud Assembly
Remove

Disconnection of the battery affects certain
vehicle electronic systems. Refer to 1.1
WARNING, CAUTION and NOTES, before
removing the ground lead.
1 Disconnect the battery ground lead. Refer to 8A – Electrical Body & Chassis.
2 Remove the intake duct and mass air flow as an assembly. Refer to 6A1 Engine Mechanical.
3 Remove the coolant recovery hose from the fan shroud retaining clip.

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Engine Cooling – V6 Engine Page 6B1–51

Disassemble
1 Remove cooling fan and shroud assembly as previously described.
NOTE
Neither fan is to be separated from its fan motor.
The assembly is carefully balanced during
manufacture and duplicating this balance on
reassembly, is not possible.
2 Remove the motor assembly wiring harness (1) from the integral clips that form a part of the shroud (2).
3 Remove screws (3) attaching the motor assembly (to the shroud, then remove each motor, fan and wiring
assembly (4) from the shroud.


Figure 6B1 –
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58
Reassemble
Reassembly is the reverse of disassembly procedures, noting the following points:
1 Tighten motor to shroud attaching screws to the correct torque specification. Do not over-tighten.
Fan motor to shroud screw
torque specification ................................................5 N.m
2 Ensure that all wiring is routed correctly and secured by the shroud clips.
3 Install cooling fan and shroud assembly to the radiator, as previously described.
3.14 Flexible Transmission Cooler Hose
Replace
NOTE
The flexible hoses are not serviced separately.
Therefore, should a hose require replacement,
then the hose and radiator to hose cooler pipe
assembly must be fitted.
1 Place a drip tray beneath the engine and radiator section.

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Engine Cooling – V6 Engine Page 6B1–53

NOTE
Should the spring clip or the O-ring seal in the
quick connect fitting be damaged during the line
removal process, then the complete fitting must
be replaced.
Reinstall
1 Remove the plugs installed in the transmission cooler line and hose openings and wipe all exposed parts
with a clean shop rag.
• Smear clean automatic transmission fluid on
each cooler line end, then push into the radiator
quick connect fittings. As a security check gently
pull on the connector to ensure correct
engagement.
• As a security check, push and clip each
verification disc into place over the quick-
connect fittings. If difficulty is experienced,
repeat the installation process until the
verification disc can be clipped into place over
the radiator quick-connect fitting.

If the verifier disc does not clip into place,
the quick-connect fitting is not engaged,
rectify this before proceeding.
• Snap the outlet cooler line (4) in the clip (5) of
the radiator fan shroud
• At the transmission end, again clean the line
ends and proceed as detailed in step 2. As a
further security check ensure that each
verification disc can be pushed into place over
the quick connect fitting. If difficulty is
experienced, then the line has not been
completely installed. Remove and repeat the
installation process again until the verification
disc can be clipped into place over the
transmission quick connect fitting
• Ensure that all line clamps are fitted correctly
and that the lines and hoses are correctly routed
and free of obstructions
• Tighten the screw attaching the cooler lines
bracket to the correct torque specifications
• If required, top up the transmission fluid level
(cold)
• Start the engine and check for any fluid leak at
the fittings. If a leak is found, stop the engine
and rectify the leak
Figure 6B1 – 61

Transmission cooler lines bracket
attaching screw torque specification ..................23.0 Nm


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Engine Cooling – V6 Engine Page 6B1–56

Reinstall
Installation of the radiator is the reverse of removal procedures, noting the following points:
1 Before installing radiator, inspect core to ensure that there is no foreign matter in core fins. Clean out between core fins with compressed air, blowing from rear to front.
2 If the vehicle is fitted with an automatic transmission, remove plugs from the removed cooling pipe ends and the two quick connect fittings.
3 After wiping cooler line ends and smearing clean automatic transmission fluid over each flared line end, push into the quick connect fitting to engage. As a security check, tug on each line to ensure correct engagement.
4 Check the transmission fluid level. Refer to the following references as required:
• 7C4 Automatic Transmission
• 4L60E On-vehicle Servicing
5 Install the following hoses:
a. Lower radiator hose, securing with the hose clamp.
b. Upper radiator hose, securing with the hose clamp.
6 Install the radiator cooling fan and shroud assembly. Refer to 3.13Cooling Fan and Shroud Assembly in this Section. Ensure that electrical connectors and the transmission cooler lines are seated correctly in the integral
retainer clips before install upper radiator shroud.
7 Refill cooling system. Refer to 3.3 Draining and Filling Cooling System in this Section.
8 Check for coolant leaks. Refer to 3.7 Pressure Testing in this Section.
9 Reconnect battery ground lead. Refer to 8A Electrical Body & Chassis.
10 Check cooling fan operation. Refer to 6C1-2 Engine Management Diagnostics. Also check for correct rotational direction of cooling fan.

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