Isuzu KB P190. Service manual — part 790

Engine Cooling – V6 Engine

Page 6B1–25

3.4

Cleaning Cooling System

N O T E

• 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.

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.

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.

Engine Cooling – V6 Engine

Page 6B1–28

3.5

Drive Belt Tension

An automatic tensioner assembly provides drive belt tension. The tensioner is an idler pulley mounted on a spring-loaded
arm that maintains the drive belt at the proper tension, without imposing undue loads on the various components.

Throughout its functional travel, the tensioner mechanism
will maintain correct belt tension, using a pulley (1) mounted
to a spring-loaded arm (2), which compensates for increases
in belt wear and stretch.

When the indicator pointer (3) on the tensioner has reached
minimum tension range (4), the tensioner has reached the
full extent of its travel and replacement of the belt (5) is
necessary.

The maximum tension range is shown at (6).

Drive belt tension can be checked using Tool No. BT3373-F.
Refer to 6A1 Engine Mechanical.

Figure 6B1 – 25