Isuzu Trooper (1998-2002 year). Manual - part 575

6B – 8 ENGINE COOLING

INSTALLATION

1. Thermostat

1) The jiggle valve of the thermostat must face the

cylinder head side.

2. Gasket
3. Install thermostat housing and tighten bolt to the

specified torque.

Torque: 20 N·m (2.0 kg·m/14 lb ft)

4. Reconnect water hose

1) Fill coolant to full level.
2) Reconnect battery ground cable.

5. Start the engine check for coolant leakage.

ENGINE COOLING  6B – 9

RADIATOR

REMOVAL

1. Disconnect battery ground cable
2. Loosen drain plug to drain coolant.
3. Radiator Hose

1) Disconnect lower hose and upper hose from the

engine.

4. Fan Guide

1) Remove clips on both sides and the bottom lock.

5. Reservoir Tank Hose

1) Disconnect the hose from radiator.

6. Bracket
7. Radiator Assembly

1) Remove the radiator assembly upward by the

hoses taking care not to damage the radiator
core by the fan blade.

2) Remove rubber cushions on both sides of the

bottom.

INSPECTION

Radiator Cap

1) Measure the valve opening pressure with the

radiator cap tester. Replace the radiator cap if it
exceeds the standard.

Valve opening pressure: 93.2 – 122.7 kPa

(0.95 – 1.25 kg/cm

2

/ 

13.5 – 17.8 psi)

Check the condition of the negative pressure valve in
the center of the valve seat side of the cap. If the valve
seat does not move smoothly due to rust or dust, clean
and replace the radiator cap.

Radiator Core

1) Deformed radiator fins could reduce radiation

effects, resulting in overheating. Straighten the fins.
In such a case, take care not to damage the fin
roots.

2) Remove dust and other foreign materials.

Flushing the Radiator

1) Wash the inside of radiator and the coolant

passage with water and a neutral detergent.
Remove all scales and rust.

110RW017

110RS006

6B – 10 ENGINE COOLING

Checking for Coolant Leakage

1) Check the cooling system for leakage with the

radiator cap tester by applying 196.0 kPa (28.4 psi)
air pressure from filler neck to inside the radiator.

INSTALLATION

1. Radiator Assembly

1) Install rubber cushions on both sides of radiator

bottom.

2) Install radiator assembly with hose, taking care

not to damage the radiator core by a fan blade.

2. Bracket

1) Support the radiator upper tank with the bracket

and fix the radiator.

3. Reserve Tank Hose
4. Fan Guide, Lower
5. Radiator Hose

1) Connect inlet hose and outlet hose to the

engine.

2) Connect battery ground cable.
3) Pour coolant up to filler neck of radiator, and up

to MAX mark of reserve tank.

4) Start engine to warm up, and check for coolant

level. Replenish coolant if it does not reach the
radiator filler neck, and tighten the cap
completely.

110RS005

012RW080

ENGINE COOLING  6B – 11

DRIVE BELT ADJUSTMENT

INSPECTION

Check drive belts for wear or damage, and replace with
new ones as necessary. Check belts for tension, and
adjust as necessary.

1) Check drive belt tension.
2) Push the middle of belt with a force of 98 N

(10 kg/22 lb) and check each belt for deflection.

Standard deflection:

For A.C. generator & fan pulley drive belt

Initial tension : 8 – 12 mm (0.31 – 0.47 in)
Tension at readjustment : Same as above.

For A/C compressor drive belt

Initial tension : 7 – 10 mm (0.28 – 0.38 in)
Tension at readjustment : 5 – 8 mm (0.20 – 0.31 in)

TENSION ADJUSTMENT

1) Loosen AC generator mounting bolt to move AC

generator, adjust belt tension and tighten to the
specified torque.

Legend

(1) Crankshaft Pulley
(2) A.C. Generator Pulley
(3) Cooling Fan Pulley

5

3

1

2

4

Legend

(1)

Crankshaft Pulley

(2)

A.C. Generator

(3)

Cooling Fan Pulley

(4)

A/C Compressor

(5)

Belt Tensioner Pulley

012RW085

3

2

1

012RW084