tow ISUZU TROOPER 1998 Service Repair Manual

1B Ð 48 AIR CONDITIONING
1
2
3
Removal Steps
1. Control lever assembly
2. A/C switch
3. Illumination bulb
Installation Steps
To install, follow the removal steps in the
reverse order.
A/C SWITCH AND ILLUMINATION BULB
REMOVAL
Preparation:
Disconnect the battery ground cable
1. Control Lever Assembly
Refer to Section 1A ÒCONTROL LEVER ASSEMBLYÓ
removal procedure.
2. A/C Switch
Raise up the catch portion of the switch and remove
the switch while pushing it toward the outside.
3. Illumination Bulb
Turn the illumination bulb counterclockwise to
remove.
Catch portion
End of switch A/C switch
INSTALLATION
To install, follow the removal steps in the reverse order.

COMPRESSOR OVERHAUL 1D Ð 23
7. Remove and discard the seal seat O-ring (2) from the
compressor neck using O-ring remover J-9553-01.
8. Recheck the shaft and inside of the compressor
neck for dirt or foreign material and be sure these
areas are perfectly clean before installing new parts.
Cleaning
Thoroughly clean O-ring seal groove in front head.
CAUTION: Seals should not be re-used. Always use
a new specification service seal on rebuild. Be sure
that the seal to be installed is not scratched or
damaged in anyway. Make sure that the seal seat
and seal are free of lint and dirt that could damage
the seal surface or prevent sealing.
Installation
1. Dip the new seal seat O-ring (1) in clean 525
viscosity refrigerant oil and assemble onto O-ring
installer J-33011.2. Insert the O-ring installer J-33011 into the
compressor neck until the installer "bottoms". Lower
the moveable slide of the O-ring installer to release
the O-ring into the seal O-ring lower groove (The
compressor neck top groove is for the shaft seal
retainer ring.) Rotate the installer to seat the O-ring
and remove the installer.
3. Dip the new seal in clean 525 viscosity refrigerant oil
and assemble seal to Seal Installer J-23128-A, by
turning handle clockwise. The stamped steel case
side of the lip seal must be engaged with knurled
tangs of installer so that flared-out side of lip seal is
facing and installed towards the compressor. Install
seal protector J-34614, in the seal lip and place over
the compressor shaft, and push the seal in place with
a rotary motion or place the seal protector J-34614
over end of compressor shaft, and slide the new seal
onto the shaft with a rotary motion until it stops. Take
care not to dislodge the O-ring. Be sure the seal (2)
makes good contact with the O-ring. Disengage the
installer from the seal and remove the installer
J-23128-A and the seal protector J-34614.
CAUTION: Handling and care of seal protector is
important. If seal protector is nicked or the bottom
flared, the new seal may be damaged during
installation.
4. Install the new seal retainer ring with its flat side
against the Seal, using Snap-Ring Pliers. Use the
sleeve from O-ring installer J-33011 to press in on
the seal retainer ring so that it snaps into its groove.
5. To leak test, install compressor leak test fixture
J-39893 on rear head of compressor and connect
gage charging lines and Refrigerant Recovery
System. Pressurize suction and high-side of
compressor with R-134a Refrigerant. Temporarily
install (M9 ´1.25 thread on shaft) nut and, with the
compressor in horizontal position, rotate the
compressor shaft in normal direction of rotation
several times by hand. Leak test the seal area and
correct and leak found. Recover the refrigerant.
Remove shaft nut.
2 J-9553-01
901RW009
1
J-33011
901RW010
J-34614
2
J-23128-A
901RW011

2A – 2 FRONT END ALIGNMENT
GENERAL DESCRIPTION
“Front End Alignment” refers to the angular relationship between the front wheels, the front suspension
attaching parts and the ground.
Proper front end alignment must be maintained in order to insure efficient steering, good directional
stability and to prevent abnormal tire wear.
The most important factors of front end alignment are wheel toe-in, wheel camber and axle caster.
DEFINITION OF TERMS
CAMBER
Camber is the inward or outward tilting of the front wheels
from the vertical. When the wheels tilt outward at the top,
the camber is positive (+). When the wheels tilt inward at
the top, the camber is negative (–). The amount of tilt
measured in degrees from the vertical is called the camber
angle.
If camber is extreme or unequal between the wheels,
improper steering and excessive tire wear will result.
Negative camber causes wear on the inside tire, while
positive camber causes wear to the outside.
CASTER
Caster is the tilting of the wheel axis either forward or
backward from the vertical (when viewed from the side of
the vehicle). A backward tilt is positive(+) and a forward tilt
is negative(–).
On the short and long arm type suspension you cannot
see a caster angle without a special instrument, but if you
look straight down from the top of the upper control arm
to the ground, the ball joints do not line up (fore and aft)
when a caster angle other than 0 degree is present. With a
positive angle, the lower ball joint would be slightly ahead
(toward the front of the vehicle) of the upper ball joint
center line.
TOE-IN
Toe-in is the turning of the front wheels. The actual
amount of toe-in is normally a fraction of a degree. Toe-in
is measured from the center of the tire treads or from the
inside of the tires. The purpose of toe-in is to insure
parallel rolling of the front wheels and to offset any small
deflections of the wheel support system which occurs
when the vehicle is rolling forward. Incorrect toe-in results
in excessive toe-in and unstable steering. Toe-in is the last
alignment to be set in the front end alignment procedure.

BLEEDING THE POWER
STEERING SYSTEM
When a power steering pump or gear has been
installed, or an oil line has been disconnected, the
air that has entered the system must be bled out
before the vehicle is operated. If air is allowed to
remain in the power steering fluid system, noisy
and unsatisfactory operation of the system may
result.
BLEEDING PROCEDURE
When bleeding the system, and any time fluid is
added to the power steering system, be sure to use
only power steering fluid as specified in
“MAINTENANCE AND LUBRICATION” in section
0B.
1. Fill the pump fluid reservoir to the proper
level and let the fluid settle for at least two
minutes.
2. Start the engine and let it run for a few
seconds.
Do not turn the steering wheel. Then turn the
engine off.
3. Add fluid if necessary.
4. Repeat the above procedure until the fluid
level remains constant after running the
engine.
5. Raise the front end of the vehicle so that the
wheels are off the ground.
6. Start the engine. Slowly turn the steering
wheel right and left, lightly contacting the
wheel stops.
7. Add power steering fluid if necessary.
8. Bring down the vehicle, set the steering wheel
at the straight forward position after turning it
to its full steer positions 2 or 3 times, and stop
the engine.
9. Stop the engine. Check the fluid level and
refill as required.
10. If the fluid is extremely foamy, allow the
vehicle to stand a few minutes and repeat the
above procedure.
INSPECT
•Belt for tightness.
•Pulley for looseness or damage. The pulley
should not wobble with the engine running.
•Make sure that hose and pipes are properly
fitted.
•Fluid level and fill to the proper level.
FLUSHING THE POWER
STEERING SYSTEM
1. Raise the front end of the vehicle off the
ground until the wheels are free to turn.
2. Remove the fluid return line at the reservoir
inlet connector and plug the connector.
Position the line toward a large container to
catch the draining fluid.
3. While running the engine at idle, fill the
reservoir with new power steering fluid. Turn
the steering wheel in both directions. Do not
contact wheel stops or hold the wheel in a
corner, or fluid will stop and the pump will be
in pressure relief mode. A sudden overflow
from the reservoir may develop if the wheel is
held at a stop.
4. While refilling the reservoir, check the
draining fluid for contamination. If foreign
material is still evident, replace all lines,
disassemble and clean or replace the power
steering system components. Do not re-use
any drained power steering fluid.
5. Install all the lines and hoses. Fill the system
with new power steering fluid and bleed the
system as described in “Bleeding The Power
Steering System”. Operate the engine for
about 15 minutes. 2A – 12 POWER STEERING
ON-VEHICLE SERVICE

POWER STEERING 2A – 27
7. O-ring
6. Top Cover Assembly
Top Cover Bolt Torque N·m (kg·m/lb·ft)
47 (4.8 / 35)
5. Lock Nut
Adjust the backlash between the worm gear and the
ball nut.
1) With the worm gear rotating, set it to the straight
ahead position.
2) Set the worm shaft preload to below 1N·m
(10kg·cm / 9 lb·in) with the sector shaft adjusting
screw.
3) Measure the worm shaft preload with the worm
gear turned 450°both to the right and to the left.
The worm gear preload in these positions should
be 0.4 - 0.6 N·m (4 - 6 kg·cm / 3.5 - 5.2 lb·in) lower
than in the straight ahead position.
4) Lock the sector shaft adjusting screw with the lock
nut.
Lock Nut Torque N·m (kg·m/lb·ft)
41 (4.2 / 30)
4. Oil Seal
Installer: 5-8522-0026-0 (J-26508)
3. Back up Ring
Position the chamfered face (outer circumference)
towards the oil seal.
2. Retaining Ring
position the chamfered face (outer circumference)
toward the oil seal.
1. Dust Cover

4A1±15 DIFFERENTIAL (FRONT)
8. Select the shim using the chart;
Pinion marking+10+8+6+4+20±2±4±6±8±10
Dial indicator
reading
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)mm
(Inches)
0.0812.18
(0.0858)
0.0822.18
(0.0858)2.20
(0.0866)
0.0832.18
(0.0858)2.20
(0.0866)2.23
(0.0882)
0.0842.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)
0.0852.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)
0.0862.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)
0.0872.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)
0.0882.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)
0.0892.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)
0.0902.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)
0.0912.18
(0.0858)2.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)
0.0922.20
(0.0866)2.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)
0.0932.24
(0.0882)2.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)
0.0942.26
(0.0890)2.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)
0.0952.28
(0.0898)2.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)
0.0962.32
(0.0914)2.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0972.34
(0.0921)2.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0982.36
(0.0929)2.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0992.38
(0.0937)2.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
02.42
(0.0953)2.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0012.44
(0.0961)2.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0022.46
(0.0969)2.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0032.48
(0.0977)2.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0042.52
(0.0992)2.54
(0.1000)2.56
(0.1008)
0.0052.54
(0.1000)2.56
(0.1008)
0.0062.56
(0.1008)
NOTE: When ordering shims, find the part number in the
parts catalog by using the thickness of shims listed in the
above table.4. Place the shim on the drive pinion, with the chamfered
side turned towards the pinion head then install the
inner bearing onto the pinion using an installer
9±8522±1165±0 and a press.

4A2A±16
DIFFERENTIAL (REAR 220mm)
4. Place the shim on the drive pinion, with the chamfered
side turned towards the pinion head then install the
inner bearing onto the pinion using an installer
9±8522±1165±0 and a press.
NOTE: Do not apply pressure to the roller cage and apply
pressure only to the inner race.
425RW048
5. Discard the used collapsible spacer and install a new
one.
6. Install pinion gear.
7. Install outer bearing.
8. Use oil seal installer 5±8840±2165±0 to install a new
oil seal that has been soaked in rear axle lubricant.
NOTE: Take care to use a front differential oil seal, NOT
the rear differential oil seal.
415RW029
9. Install dust cover.
10. Install flange.
11. Install flange nut.
1. Apply lubricant to the pinion threads.2. Tighten the nut to the specified torque using the
pinion flange holder 5±8840±2157±0.
Torque: 245±294N´m (25.0±28.0kg´m/181±217 lb f
t)
NOTE: Discard used flange nut and install new one and
do not over tighten the flange nut.
425RW057
3. Adjust pinion bearing preload.
a. Measure the bearing preload by using a torque
meter. Note the scale reading required to
rotate the flange.
b. Continue tightening flange nut until the
specified starting torque is obtained.
Starting torque:
New bear-
ing 0.7±1.3 N´m(0.07-0.13kg´m/6.08±11.28 lb in)
Used bear-
ing 0.4±0.6N´m(0.04±0.06kg´m/3.04-5.64 Ib in)
425RS027
4. Using punch 5±8840±2293±0, stake the flange
nut at two points.

4A2B±24DIFFERENTIAL (REAR 244mm)
4. Remove Differential shaft (2) using hammer and
punch.
Place shop towel behind case to prevent differential
shaft from dropping out of case.
425RW005
5. Assemble clutch pack unloading tool
5±8840±2586±0 .
a. Install cap (1) to the bottom differential side gear.
b. Install threaded screw cap (2) to top differential
side gear. Thread forcing screws (3) into threaded
screw cap until it becomes centered into the
bottom cap.
425RW064
c. Tighten forcing screw until tight enough to collapse
dished spacers and allow looseness between side
and pinion mate gears.6. Both pinion mate gear thrust washers using a shim
stock (1) of 0.51 mm (0.020 in.) or equivalent tool to
push out washers.
425RW007
7. Relieve tension of dished spacers by loosening
forcing screw.
NOTE:

You may have to adjust the forcing screw slightly to
allow the case to rotate.
8. Insert differential shaft into its hole of case. Pull on
shaft and rotate case until pinion mate gears can be
removed.
9. Remove pinion mate gears.
10. Hold side gear top clutch pack (1) with one hand and
remove positraction unloading tools.
425RW008

4C±17 DRIVE SHAFT SYSTEM
11. Install follower to clutch so that follower nails (large)
(1) will come closer to the bent portion of retaining
spring by aligning follower stopper nail with outer
teeth of clutch. Then, fit in with follower's nails (small)
(2) caught in spring.
411RW016
12. Install compression ring.
Turn the smaller diameter side toward follower and fit
spring in clutch.
13. Align follower nail (1) to handle groove (2). and then
assemble clutch with knob by pushing and turning
clutch counterclockwise to knob.
411RW017
14. Install gasket.
Make sure that there is no breakage, etc.
15. Install outer bearing outer race by driving it into the
hub, by using installer 5±8522±2118±0 and grip
5±8840±0007±0.
411RW007
16. Install inner bearing outer race by driving it into the
hub, by using installer 5±8840±2119±0 and grip
5±8840±0007±0.
411RW006

5A±4
BRAKE CONTROL SYSTEM
normal braking when a malfunction has occurred in the
ABS.
The EHCU has a self-diagnosing function which can
indicate faulty circuits during diagnosis.
The EHCU is mounted on the engine compartment front
right side. It consists of a Motor, Plunger Pump, Solenoid
Valves and Check Valve.
On the outside, the relay box containing a motor relay and
a valve relay is installed.
Solenoid Valves: Reduces or holds the caliper fluid
pressure for each front disc brake or both rear disc brakes
according to the signal sent from the EHCU.
Reservoir: Temporarily holds the brake fluid that returns
from the front and rear disc brake caliper so that pressure
of front disc brake caliper can be reduced smoothly.
Plunger Pump: Feeds the brake fluid held in the reservoir
to the master cylinder.
Motor: Drives the pump according to the signal from
EHCU.
Check Valve: Controls the brake fluid flow.
ABS Warning Light
821RW033Vehicles equipped with the Anti-lock Brake System have
an amber ªABSº warning light in the instrument panel.
The ªABSº warning light will illuminate if a malfunction in
the Anti-lock Brake System is detected by the Electronic
Hydraulic Control Unit (EHCU). In case of an electronic
malfunction, the EHCU will turn ªONº the ªABSº warning
light and disable the Anti-lock braking function.
The ªABSº light will turn ªONº for approximately three
seconds after the ignition switch is to the ªONº position.
If the ªABSº light stays ªONº after the ignition switch is the
ªONº position, or comes ªONº and stays ªONº while
driving, the Anti-lock Brake System should be inspected
for a malfunction according to the diagnosis procedure.
Wheel Speed Sensor
It consists of a sensor and a rotor. The sensor is attached
to the knuckle on the front wheels and to the axle shaft
bearing holder on the rear wheels.
The rotor is press-fit in the axle shaft.The flux generated from electrodes magnetized by a
magnet in the sensor varies due to rotation of the rotor,
and the electromagnetic induction generates alternating
voltage in the coil. This voltage draws a ªsine curveº with
the frequency proportional to rotor speed and it allows
detection of wheel speed.
G-Sensor
The G-sensor installed inside the center console detects
the vehicle deceleration speed and sends a signal to the
EHCU. In 4WD operation, all four wheels may be
decelerated in almost the same phase, since all wheels
are connected mechanically.
This tendency is noticeable particularly on roads with low
friction coefficient, and the ABS control is adversely
affected.
The G-sensor judges whether the friction coefficient of
road surface is low or high, and changes the EHCU's
operating system to ensure ABS control.
Normal and Anti-lock Braking
Under normal driving conditions, the Anti-lock Brake
System functions the same as a standard power assisted
brake system. However, with the detection of wheel
lock-up, a slight bump or kick-back will be felt in the brake
pedal. This pedal ªbumpº will be followed by a series of
short pedal pulsations which occurs in rapid succession.
The brake pedal pulsation will continue until there is no
longer a need for the anti-lock function or until the vehicle
is stopped. A slight ticking or popping noise may be heard
during brake applications when the Anti-lock features is
being used.
When the Anti-lock feature is being used, the brake pedal
may rise even as the brakes are being applied. This is
also normal. Maintaining a constant force on the pedal
will provide the shortest stopping distance.
Brake Pedal Travel
Vehicles equipped with the Anti-lock Brake System may
be stopped by applying normal force to the brake pedal.
Although there is no need to push the pedal beyond the
point where it stops or holds the vehicle, by applying more
force the pedal will continue to travel toward the floor.
This extra brake pedal travel is normal.
Acronyms and Abbreviations
Several acronyms and abbreviations are commonly used
throughout this section:
ABS
Anti-lock Brake System
CKT
Circuit
DLC
Data Link Connector
EHCU
Electronic Hydraulic Control Unit
FL
Front Left