cooling ISUZU TROOPER 1998 Service Owner's Manual

1BÐ74 AIR CONDITIONING
FUNCTIONS AND FEATURES
¥ Automatic interior temperature control
This function enables to maintain the interior temperature at the level specified from the temperature
control switch despite of changes in factors such as vehicle speeds, outside air temperature and number
of passengers.
¥ Maximum cooling and heating function
You can select FC (Full cool, namely maximum cooling temperature) or FH (Full heat, maximum heating
temperature) from the temperature control lever.
¥ Automatic air flow control
Air flow is automatically and consecutively fine tuned according to the specified interior temperature and
changes in aperture of the heater unit mix door.
¥ Mode (blow port) control
This function automatically selects either one of the VENT, BI-LEVEL, FOOT or DEP mode for the blow
port according to changes of temperature on the blow port. Using the mode switch allows you to select a
desired blow port manually.
¥ Intake (switching between the fresh air intake and circulation of interior air) control
The intake (switching between fresh air intake and circulation of interior air) mode automatically selects
either FRESH (fresh air intake), MIX or RECIRC (interior air circulation) according to changes of the blow
port temperature. Using the intake switch allows you to select a desired intake port manually (in the
manual operation, FRESH and RECIRC modes alone are available). Pressing the DEF (defrost) mode
switch selects the FRESH (fresh air intake).
¥ Cooler start-up timing control
This function is used for maintaining the air flow at "LOW" level until the evaporator is sufficiently cooled
down. It is intended to prevent a large volume of hot air being blowing into inside of a vehicle when the
cooler is turned on in hot summer season.
¥ Heater start-up timing control
This function is used for maintained the air flow at "LOW" level and also for maintaining the defrost
mode until temperature of coolant in the heater core is sufficiently heated. It is intended to prevent a
large volume of cool air being blown into inside of a vehicle when the heater is turned on in cold winter
season.
¥ Solar radiation quantity offset control
The photodiode on the solar radiation sensor determines solar radiation quantity accurately to offset
interior temperature quickly.
¥ Switch position storing function
This function is used for storing switch positions being selected in the immediately preceding operation,
namely the last time the ignition has been turned off. It simplifies the setup procedures when restarting
the system.
¥ Self-diagnosis function
The self-diagnosis function turned on from the panel switch makes your troubleshooting easier (for detail
of this function, refer to the section titled "Self-Diagnosis").

AIR CONDITIONING 1BÐ91
6. Heating Start Timing Control
When the automatic heater/air conditioner is
started, heating is turned on under following
conditions.
·The detected temperature of thermo unit is
136¡F or less.
·The temperature setting signal and the total
signal by each sensor meet the condition of
heating.
When the detected temperature by the coolant
temperature sensor is 136¡F or less the blower
fan motor is set to work at low speed and the
"DEF" mode is selected.
When the detected temperature by the coolant
temperature sensor is 77¡F or more, the blow
mode changes automatic control. And the
blower fan speed is controlled to be lineally up
from "LO" to "MAX HI".7. Cooling Start Timing Control
When the automatic heater/air conditioner is
started, cooling is turned on under following
conditions.
·The in car sensor is 86¡F or more.
·The temperature setting signal and the signals
from each sensor meet the specified condition.
The blower fan speed is set to "LO" for
maximum 7 seconds when cooling start
conditions meet, and then, is controlled to be
lineally up to "MAX HI" by 5.32%/S.
Ignition swich
"ON"
Time
Blower voltage to turn
on the cooling
7 SEC maximum3 SEC
100%
(MAX HI)
33.5%
(LO)5.32%/S
C06RY00001
33.5%
(LO)
2.63%/S
Mode
DEF
Auto
Mode
100%
(MAX HI)
Ignition
switch "ON"
Thermo Unit 58¡C(Gasoline)
52¡C(Diesel) Time
840RY00009

1BÐ92 AIR CONDITIONING
TROUBLESHOOTING
Troubleshooting, Its Overview and Procedures
The full automatic heater and air conditioner equips with the "Self-Diagnosis Function" to check its major
components.
This function makes access to the sensors, actuators and blower fan motor system easier when checking
them up and, when a failed part is located, this function restores its original performance.
When implementing the troubleshooting, this self-diagnosis function narrows the range to be searched at
the first step, then check relevant parts one by one according to the "Checking Procedures by Failed
Location" As for a location this function is unappreciable, the system accurately determines characteristics
of a given trouble and checks relevant parts according to the "Checking Procedures by Failed Location".
The following illustrates basic troubleshooting flow.
1. Basic Troubleshooting Flow
Occurrence of a trouble
Refer to the check list for
the inspection.Locate the failed location.
Check the failed part.
Correction
Correction
Correction
Troubleshooting by the
self-diagnosis function.Reference the "Check
Procedure by Failed
Location" for the inspection.
Reference the "Check
Procedure by Failed
Location" for the inspection.Correction
Check the cooling / heating
cycles.
End OK OK OK OKNG
NG
NG
NG
NG OK
Check if the automatic
heater / air conditioner
control unit indicator LED
is turned on.Check the power supply and
circuit on the automatic
heater / air conditioner control
unit.
Troubleshooting not relying
on the self-diagnosis
function(troubleshooting
by failure type).
F01RX009

POWER STEERING 2A – 13
STEERING GEAR
Removal Steps
1. Pipe
2. Nut
3. Pitman arm
4. Universal joint bolt
5. Gear box mounting bolt and nut
6. Gear box
Installation Steps
6. Gear box
5. Gear box mounting bolt and nut
4. Universal joint bolt
3. Pitman arm
2. Nut
1. Pipe
REMOVAL
Preparation:
1) Remove the stone guard.
2) Remove the lower fan shroud. Refer to “Engine
cooling” in section 6B1.
3) Disconnect stabilizer bar at the stabilizer links.
Loosen stabilizer bracket fixing nuts.
1. Pipe
2. Nut
3. Pitman Arm
Pitman arm remover: 5-8840-2005-0 (J-29107)
These steps are based on the LHD model.

6A±1
ENGINE MECHANICAL
ENGINE
CONTENTS
Engine Mechanical 6A. . . . . . . . . . . . . . . . . . . . . .
Engine Cooling 6B. . . . . . . . . . . . . . . . . . . . . . . . .
Engine Fuel 6C. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Electrical 6D1. . . . . . . . . . . . . . . . . . . . . . . .
Ignition System 6D2. . . . . . . . . . . . . . . . . . . . . . . . .
Starting and Charging System 6D3. . . . . . . . . . . . Driveability and Emissions 6E. . . . . . . . . . . . . . . .
Engine Exhaust 6F. . . . . . . . . . . . . . . . . . . . . . . . .
Engine Lubrication 6G. . . . . . . . . . . . . . . . . . . . . .
Engine Speed Control System 6H. . . . . . . . . . . .
Inducton 6J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ENGINE MECHANICAL
CONTENTS
Service Precaution 6A±2. . . . . . . . . . . . . . . . . . . . . .
General Description 6A±3. . . . . . . . . . . . . . . . . . . . .
Engine Diagnosis 6A±4. . . . . . . . . . . . . . . . . . . . . . .
Cylinder Head Cover LH 6A±18. . . . . . . . . . . . . . . . .
Removal 6A±18. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±19. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cylinder Head Cover RH 6A±21. . . . . . . . . . . . . . . . .
Removal 6A±21. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±22. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Common Chamber 6A±24. . . . . . . . . . . . . . . . . . . . . .
Removal 6A±24. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±24. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust Manifold LH 6A±26. . . . . . . . . . . . . . . . . . . . .
Removal 6A±26. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±26. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust Manifold RH 6A±27. . . . . . . . . . . . . . . . . . . .
Removal 6A±27. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±27. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Crankshaft Pulley 6A±28. . . . . . . . . . . . . . . . . . . . . . .
Removal 6A±28. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±28. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Timing Belt 6A±29. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 6A±29. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±30. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Camshaft 6A±33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 6A±33. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±33. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cylinder Head 6A±37. . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 6A±37. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±37. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valve Stem Oil Controller , Valve Spring and
Valve Guide 6A±39. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 6A±39. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±39. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Piston, Piston Ring and Connecting Rod 6A±40. . . Removal 6A±40. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±41. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Crankshaft and Main Bearings 6A±42. . . . . . . . . . . .
Removal 6A±42. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±43. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Oil Seal 6A±47. . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 6A±47. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±47. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Assembly 6A±48. . . . . . . . . . . . . . . . . . . . . . . .
Removal 6A±48. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 6A±48. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cylinder Head 6A±52. . . . . . . . . . . . . . . . . . . . . . . . . .
Cylinder Head and Associated Parts 6A±52. . . . .
Disassembly 6A±52. . . . . . . . . . . . . . . . . . . . . . . . . .
Clean 6A±53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 6A±53. . . . . . . . . . . . . . . . . .
Reassembly 6A±53. . . . . . . . . . . . . . . . . . . . . . . . . .
Valve Spring, Oil Controller, Valve,
Valve Guide 6A±56. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valve Spring, Oil Controller, Valve,
Valve Guide and Associated Parts 6A±56. . . . . . .
Disassembly 6A±56. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 6A±57. . . . . . . . . . . . . . . . . .
Reassembly 6A±60. . . . . . . . . . . . . . . . . . . . . . . . . .
Valve Clearance Adjustments 6A±61. . . . . . . . . . . . .
Camshaft 6A±63. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Camshaft and Associated Parts 6A±63. . . . . . . . .
Disassembly 6A±63. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 6A±64. . . . . . . . . . . . . . . . . .
Reassembly 6A±66. . . . . . . . . . . . . . . . . . . . . . . . . .
Crankshaft 6A±69. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Crankshaft and Associated Parts 6A±69. . . . . . . .
Disassembly 6A±69. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 6A±70. . . . . . . . . . . . . . . . . .
Inspection and Repair 6A±71. . . . . . . . . . . . . . . . . .
Reassembly 6A±73. . . . . . . . . . . . . . . . . . . . . . . . . .

6A±11
ENGINE MECHANICAL
Condition CorrectionPossible cause
Engine overheatingLevel of Engine Coolant too lowReplenish
Fan clutch defectiveReplace
Incorrect fan installedReplace
Thermostat defectiveReplace
Engine Coolant pump defectiveCorrect or replace
Radiator cloggedClean or replace
Radiator filler cap defectiveReplace
Level of oil in engine crankcase too
low or wrong engine oilChange or replenish
Resistance in exhaust system
increasedClean exhaust system or replace
defective parts
Throttle Position Sensor adjustment
incorrectReplace with Throttle Valve ASM
Throttle Position Sensor circuit open
or shortedCorrect or replace
Cylinder head gasket damagedReplace
Engine overcoolingThermostat defectiveReplace (Use a thermostat set to
open at 82
C (180
F))
Engine lacks compressionÐÐÐÐRefer to Hard Start
OthersTire inflation pressure abnormalAdjust to recommended pressures
Brake dragAdjust
Clutch slippingAdjust or replace
Level of oil in engine crankcase too
highCorrect level of engine oil
Exhaust Gas Recirculation Valve
defectiveReplace
Engine Noisy
Abnormal engine noise often consists of various noises
originating in rotating parts, sliding parts and othermoving parts of the engine. It is, therefore, advisable to
locate the source of noise systematically.
Condition
Possible causeCorrection
Noise from crank journals or from
crank bearings
(Faulty crank journals and crankOil clearance increased due to worn
crank journals or crank bearingsReplace crank bearings and
crankshaft or regrind crankshaft and
install the undersize bearing
yj
bearings usually make dull noise that
becomes more evident when
accelerating)Crankshaft out of roundReplace crank bearings and
crankshaft or regrind crankshaft and
install the undersize bearing
Crank bearing seizedCrank bearing seized. Replace crank
bearings and crankshaft or regrind
crankshaft and install the undersize
bearing
Troubleshooting Procedure
Short out each spark plug in sequence using insulated
spark plug wire removers. Locate cylinder with defectivebearing by listening for abnormal noise that stops when
spark plug is shorted out.

6A±18
ENGINE MECHANICAL
Cylinder Head Cover LH
Removal
1. Disconnect battery ground cable.
2. Drain engine coolant from faucet bottom of radiator.
3. Remove engine cover from the dowels on the
common chamber.
F06RW018
4. Remove air cleaner duct assembly (3) and air cleaner
element (4).
130RW001
Legend
(1) Positive Crankcase Ventilation Hose Connector
(2) Intake Air Temperature Sensor
(3) Air Cleaner Duct Assembly
(4) Air Cleaner Element
(5) Mass Air Flow Sensor
NOTE: Disconnect the mass air flow (MAF) sensor
connector, intake air temperature (IAT) sensor connector,
and positive crankcase ventilation (PCV) hose before
hand the air cleaner duct assembly is removed.5. Disconnect following wiring connectors and bonding
cable:

Manifold Absolute Pressure (MAP) sensor

Vacuum Switching Valve (VSV) for Induction Air
Control Valve (IACV) actuator

Ignition coils for left bank

Fuel injectors for left bank

Idle air control (IAC) valve

Throttle position sensor (TPS)

Bonding cable

Others as necessitated
6. Disconnect following vacuum hoses:

Brake master VAC

Canister

VSV for IACV actuator

Duty solenoid valve

PCV
7. Disconnect radiator upper and lower hoses
8. Remove engine harness from the cylinder head
cover.
9. Remove the upper fan guide.
10. Remove cooling fan and clutch assembly.
11. Remove drive belt by pushing down the auto
tensioner using spanner as illustrated.
F06RW019

6A±19
ENGINE MECHANICAL
Legend
(1) Crankshaft Pulley
(2) Generator
(3) Auto Tensioner
(4) Idle Pulley
(5) Cooling Fan Pulley
(6) Power Steering Oil Pump
(7) Drive Belt
(8) Air Conditioner Compressor
12. Remove power steering oil pump pulley.
13. Remove fan pulley and bracket assembly.
14. Remove idle pulley assembly.
15. Remove auto tensioner assembly.
16. Remove crankshaft pulley using 5±8840±0133±0
crankshaft holder.
17. Remove timing belt covers from the right bank side to
the left bank side in order.
18. Remove ignition coil assemblies for the left side bank.
060RW018
Legend
(1) Ignition Coil Connectors
(2) Bolts
(3) Ignition Coil Assemblies
19. Remove cylinder head cover assembly.
Installation
1. Install cylinder head cover.

Clean the sealing surface of cylinder head and
cylinder head cover to remove oil and sealing
materials completely.

Apply sealant (TB-1207B or equivalent) of bead
diameter 2-3 mm at eight place of arched area of
camshaft bracket on front and rear sides.
The cylinder head cover must be installed within 5
minutes after sealant application to prevent
premature hardening of sealant.
014RW144

Tighten bolts to the specified torque.
Torque : 9 N´m (0.9 Kg´m/78 lb in)
010RW008
2. Install ignition coil assemblies and tighten the fixing
bolts to the specified torque.
Torque : 4 N´m (0.4 Kg´m/35 lb in)
3. Install timing belt covers from left bank side to right
bank side, and tighten the fixing bolts and nut to the
specified torque.
Torque : 19 N´m (1.9 Kg´m/14 lb ft)
4. Install crankshaft pulley and tighten the fixing bolt
using 5±8840±0133±0 crankshaft holder to the
specified torque.
Torque : 167 N´m (17.0 Kg´m/123 lb ft)

6A±20
ENGINE MECHANICAL
5. Install auto tensioner assembly and tighten the fixing
bolts to the specified torque.
Torque :
Shorter Bolt : 20 N´m (2.0 Kg´m/14 lb ft)
Longer Bolt : 39 N´m (4.0 Kg´m/29 lb ft)
6. Install idle pulley and bracket assembly and tighten
the fixing bolt to the specified torque.
Torque : 52 N´m (5.3 Kg´m/38 lb ft)
7. Install fan pulley and bracket assembly and tighten
the fixing bolts and nut to the specified torque.
Torque : 22 N´m (2.2 Kg´m/16 lb ft)
8. Install power steering oil pump pulley and tighten the
fixing bolt to the specified torque.
Torque : 78 N´m (8.0 Kg´m/58 lb ft)
9. Install drive belt by pushing down the auto tensioner
using spanner as shown in the removal step of drive
belt.
10. Install cooling fan and clutch assembly and tighten
the fixing bolts to the specified torque.
Torque : 10 N´m (1.0 Kg´m/87 lb in)
11. Install upper fan guide and clip both side and tighten
the fixing bolts to the specified torque.
Torque : 4 N´m (0.4 Kg´m/35 lb in)
12. Install engine harness and tighten the fixing bolts of
the retaining clip and bracket to the specified torque.
Torque : 4 N´m (0.4 Kg´m/35 lb in)
13. Connect radiator upper and lower hoses and clip
them securely.
14. Connect vacuum hoses of those which were
disconnected in the removal step.
15. Connect wiring connectors and bonding cable of
those which were disconnected in the removal step.
16. Install air cleaner element and air cleaner duct
assembly, and clip the both end securely.
17. Connect MAF sensor connector, IAT sensor
connector and PCV hose.
18. Install engine cover mating with the dowels.

6A±21
ENGINE MECHANICAL
Cylinder Head Cover RH
Removal
1. Disconnect battery ground cable.
2. Remove battery from the vehicle.
3. Drain engine coolant from faucet bottom of radiator.
4. Remove engine cover from the dowels on the
common chamber.
F06RW018
5. Remove air cleaner duct assembly (3) and air cleaner
element (4).
130RW001
Legend
(1) Positive Crankcase Ventilation Hose Connector
(2) Intake Air Temperature Sensor
(3) Air Cleaner Duct Assembly
(4) Air Cleaner Element
(5) Mass Air Flow Sensor
NOTE: Disconnect the mass air flow (MAF) sensor
connector, intake air temperature (IAT) sensor connector,
and positive crankcase ventilation (PCV) hose before
hand the air cleaner duct assembly is removed.
6. Disconnect following wiring connectors and bonding
cable:

Exhaust Gas Recirculation (EGR) valve

Fuel injectors for right bank

Ignition coils for right bank

Bonding cable

Othres as necessitated
7. Disconnect radiator upper and lower hoses.
8. Remove engine harness from the cylinder head
cover.
9. Remove the upper fan guide.
10. Remove cooling fan and clutch assembly.
11. Remove drive belt by pushing down the auto
tensioner using spanner as illustrated.
F06RW019
Legend
(1) Crankshaft Pulley
(2) Generator
(3) Auto Tensioner
(4) Idle Pulley
(5) Cooling Fan Pulley
(6) Power Steering Oil Pump
(7) Drive Belt
(8) Air Conditioner Compressor
12. Remove fan pulley and bracket assembly.
13. Remove idle pulley assembly.
14. Remove auto tensioner assembly.
15. Remove crankshaft pulley using 5±8840±0133±0
crankshaft holder.