1998 ISUZU TROOPER seat adjustment

1B Ð 6 AIR CONDITIONING
DUAL PRESSURE SWITCH
The dual pressure switch is installed on the upper
part of the receiver/drier, to detect excessively high
pressure (high pressure switch) and prevent
compressor seizure due to the refrigerant leaking
(low pressure switch), switching the compressor
ÒONÓ or ÒOFFÓ as required.
The pressure switch connector is waterproof type.
·Low-pressure control kpa (kgácm
2/ PSI)
Compressor
ON: 205.9 ± 30 (2.1 ± 0.3 / 30 ± 4)
(Except 6VD1 / 6VE1, LHD model)
186 ± 30 (1.9 ± 0.3 / 27 ± 4)
(only for 6VD1 / 6VE1, LHD model)
OFF: 176 ± 20 (1.8 ± 0.2 / 26 ± 3)
·High-pressure control
Compressor
ON: 2354 ± 196 (24.0 ± 2.0 / 341 ± 28)
OFF: 2942 ± 196 (30.0 ± 2.0 / 427 ± 28)
TRIPLE PRESSURE SWITCH
Triple pressure switch is installed atop the receiver/
drier. This switch is constructed with a unitized type
of two switches. One of them is a low and high
pressure switch (Dual pressure switch) to switch
ÒONÓ or ÒOFFÓ the magnetic clutch as a result of
irregularly high-pressure or low-pressure of the
refrigerant. The other one is a medium pressure
switch (Cycling switch) to switch ÒONÓ or ÒOFFÓ
the condenser fan sensing the condenser high side
pressure.·Low-pressure control kpa (kgácm
2/PSI)
Compressor
ON: 186 ± 30 (1.9 ± 0.3 / 27 ± 4)
OFF: 176 ± 20 (1.8 ± 0.2 / 26 ± 3)
·Medium-pressure control
Condenser fan
ON: 1471 ± 98 (15.0 ± 1.0 / 213 ± 14)
OFF: 1079 ± 98 (11.0 ± 1.0 / 156 ± 14)
·High-pressure control
Compressor
ON: 2354 ± 196 (24.0 ± 2.0 / 341 ± 28)
OFF: 2942 ± 196 (30.0 ± 2.0 / 427 ± 28)
EXPANSION VALVE
This expansion valve (1) is internal pressure type
and it is installed at the evaporator intake port.
The expansion valve converts the high pressure
liquid refrigerant sent from the receiver/drier to a
low pressure liquid refrigerant by forcing it through
a tiny port before sending it to the evaporator (2).
This type of expansion valve consists of a
temperature sensor, diaphragm, ball valve, ball
seat, spring adjustment screw, etc.
The temperature sensor contacts the evaporator
outlet pipe, and converts changes in temperature to
pressure. It then transmits these to the top chamber
of the diaphragm.
The refrigerant pressure is transmitted to the
diaphragms bottom chamber through the external
equalizing pressure tube.
The ball valve is connected to the diaphragm. The
opening angle of the expansion valve is determined
by the force acting on the diaphragm and the spring
pressure.
The expansion valve regulates the flow rate of the
refrigerant. Accordingly, when a malfunction occurs
to this expansion valve, both discharge and suction
pressures get low, resulting in insufficient cooling
capacity of the evaporator.
Pressure switch
Receiver/Drier
Triple pressure switch
Condenser fan Condenser
1
2
875RY00003874RY00003

5C – 32 POWER ASSISTED BRAKE SYSTEM
(4) When the front brake system fails.
When there is a failure in the front brake system,
the fluid pressure from the front master cylinder
decreases. As a result, the balance between the
front and rear brake side fluid pressures is lost at
the control valve sleeve so that the control valve
sleeve moves upwards.
The control valve sleeve strikes against the piston,
thereby pushing the piston upwards.
Accordingly, the fluid pressure of the rear master
cylinder is not decreased and is applied directly to
the rear wheel cylinder to secure a sufficient
braking performance of the rear brakes. (See the
left figure.)
Valve Maintenance
In the case of fluid leak or other abnormalities, faulty
valve should be replaced.
Note:
The load sensing proportioning valve is not
repairable and must be replaced as a complete
assembly.
ADJUSTMENT PROCEDURE OF LSPV
1. Adjust the rear axle weight by loading the
laggage compartmemt as necessary.
Rear Axle Weight N (kg / lb)
10,300 (1,050 / 2,315)
Note:
The rear axle weight should be adjusted to the
specified value with a man seated in the driver seat.
Rear master cylinder
fluid Pressure
C05RW022

6A±61
ENGINE MECHANICAL
5. Install lower valve spring seat, valve spring and upper
valve spring seat then put split collars on the upper
spring seat, using the 5±8840±2446±0 valve spring
compressor and 5±8840±2547±0 valve spring
compressor adapter to install the split collars.
014RW042
6. Install tappet with shim.
7. Install camshaft assembly.

Refer to installation procedure for Camshaft in this
manual.
Valve Clearance Adjustments
NOTE: To adjust valve clearance, apply engine oil to the
cam as well as to the adjusting shim (2) with the cylinder
head built on the cylinder block, give a few turns to the
camshaft by means of timing pulley tightening bolt, and
measure valve clearance when the nose of cam is just
opposite to maximum cam lift (1) as shown in illistration
below.
014RW081
Legend
(1) Cam
(2) Shim
(3) Tappet
Valve Clearance Standard Value (cold)
Intake: 0.23 mm±0.33 mm
(0.0091 in±0.0130 in)
Exhaust: 0.25 mm±0.35 mm
(0.0098 in±0.0138 in)
Selection of Adjusting Shim
Shim to be selected = (Thickness of removed shim) +
(Valve clearance measurement ± Standard valve)
Based on the above formula, the best suited shim should
be selected from 41 sorts of shim (differently thick at
0.02mm (0.0008 in) intervals from 2.40mm (0.0945 in)
through 3.2mm (0.1260 in) thick). Install the shim and
check valve clearance.

6E±341 ENGINE DRIVEABILITY AND EMISSIONS
this is done, if the problem still exists, it may be diagnosed
in the normal manner.
Electrostatic Discharge Damage
Electronic components used in the PCM are often
designed to carry very low voltage. Electronic
components are susceptible to damage caused by
electrostatic discharge. Less than 100 volts of static
electricity can cause damage to some electronic
components. By comparison, it takes as much as 4000
volts for a person to feel even the zap of a static
discharge.
TS23793
There are several ways for a person to become statically
charged. The most common methods of charging are by
friction and induction.

An example of charging by friction is a person sliding
across a vehicle seat.

Charge by induction occurs when a person with well
insulated shoes stands near a highly charged object
and momentary touches ground. Charges of the
same polarity are drained off leaving the person
highly charged with the opposite polarity. Static
charges can cause damage, therefore it is important
to use care when handling and testing electronic
components.
NOTE: To p r e ve n t p ossible electrostatic discharge
damage, follow these guidelines:

Do not touch the PCM connector pins or soldered
components on the PCM circuit board.

Do not touch the knock sensor module component
leads.

Do not open the replacement part package until the
part is ready to be installed.

Before removing the part from the package, ground
the package to a known good ground on the vehicle.

If the part has been handled while sliding across the
seat, while sitting down from a standing position, or
while walking a distance, touch a known good ground
before installing the part.
Upshift Lamp
Refer to Manual Transmission.
General Description (Air Induction)
Air Induction System
The air induction system filters contaminants from the
outside air, and directs the progress of the air as it is
drawn into the engine. A remote-mounted air cleaner
prevents dirt and debris in the air from entering the
engine. The air duct assembly routes filtered air to the
throttle body. Air enters the engine by to following steps:
1. Through the throttle body.
2. Into the common chamber.
3. Through the cylinder head intake ports.
4. Into the cylinders.
055RV010
General Description (Fuel Metering)
Acceleration Mode
The PCM provides extra fuel when it detects a rapid
increase in the throttle position and the air flow.
Accelerator Controls
The accelerator control system is a cable-type system
with specific linkage adjustments.
Refer to
Cable Adjustment.
Battery Voltage Correction Mode
When battery voltage is low, the PCM will compensate for
the weak spark by increasing the following:

The amount of fuel delivered.

The idle RPM.

Ignition dwell time.
CMP Signal
The PCM uses this signal to determine the position of the
number 1 piston during its power stroke, allowing the

6E±348
ENGINE DRIVEABILITY AND EMISSIONS
oil to enter the cylinder, particularly if the deposits are
heavier on the side of the spark plug facing the intake
valve.
TS23995
Excessive gap means that the air space between the
center and the side electrodes at the bottom of the spark
plug is too wide for consistent firing. This may be due to
improper gap adjustment or to excessive wear of the
electrode during use. A check of the gap size and
comparison to the gap specified for the vehicle in
Maintenance and Lubrication will tell if the gap is too wide.
A spark plug gap that is too small may cause an unstable
idle condition. Excessive gap wear can be an indication
of continuous operation at high speeds or with engine
loads, causing the spark to run too hot. Another possible
cause is an excessively lean fuel mixture.
TS23992
Low or high spark plug installation torque or improper
seating can result in the spark plug running too hot and
can cause excessive center electrode wear. The plug
and the cylinder head seats must be in good contact for
proper heat transfer and spark plug cooling. Dirty or
damaged threads in the head or on the spark plug cankeep it from seating even though the proper torque is
applied. Once spark plugs are properly seated, tighten
them to the torque shown in the Specifications Table. Low
torque may result in poor contact of the seats due to a
loose spark plug. Overtightening may cause the spark
plug shell to be stretched and will result in poor contact
between the seats. In extreme cases, exhaust blow-by
and damage beyond simple gap wear may occur.
Cracked or broken insulators may be the result of
improper installation, damage during spark plug
re-gapping, or heat shock to the insulator material. Upper
insulators can be broken when a poorly fitting tool is used
during installation or removal, when the spark plug is hit
from the outside, or is dropped on a hard surface. Cracks
in the upper insulator may be inside the shell and not
visible. Also, the breakage may not cause problems until
oil or moisture penetrates the crack later.
TS23994
A broken or cracked lower insulator tip (around the center
electrode) may result from damage during re-gapping or
from ªheat shockº (spark plug suddenly operating too
hot).
TS23993

00 Ð 6 SERVICE INFORMATION
Checkpoint Possible cause Correction
Injection timing improperly adjusted Adjust the injection timing
Insufficient injection volume Adjust the injection volume
Defective idle spring Replace the idle spring
Defective governor lever operation Repair or replace the governor
lever
Regulator valve improperly adjustment Adjust or replace the regulator valve
Broken plunger spring Replace the plunger spring
Worn plunger Replace the plunger assembly
Worn cam disc Replace the cam disc
Valve clearance improperly adjusted Adjust the valve clearance Valve clearance
Blown out cylinder head gasket. Worn
cylinder liner.
Piston ring sticking between
the valve and the valve seatReplace the related parts Compression
pressure
Fuel system leakage or blockage Repair or replace the fuel system Fuel system
Air in the fuel system Bleed the air from the fuel system
Water particles in the fuel system Change the fuel
Clogged fuel filter element Replace the fuel filter element or
the fuel filter cartridge Fuel filter
Defective fuel feed pump Repair or replace the fuel feed pump Fuel feed pump
Injection nozzle sticking Replace the injection nozzle Injection nozzle
Injection nozzle injection starting pressure
too low
Improper spray conditionAdjust or replace the injection
nozzle
Defective delivery valve resulting in fuel
drippage after fuel injectionReplace the delivery valve Injection pump

ENGINE MECHANICAL 6A Ð 3
INSPECTION AND REPAIR
Make the necessary adjustments, repairs, and part re-
placements if excessive wear or damage is discovered
during inspection.
·Cylinder head gasket and mating surfaces for leaks,
corrosion and blow-by. If the gasket has failed,
determine the cause;
Ð Improper installation
Loose or warped cylinder head
Ð Insufficient torque on head bolts
Ð Warped case surface
1. Cylinder head bolts for damaged threads or stretch-
ing and damaged heads caused by improper use of
tools.
CAUTION:
Suspected bolts must be replaced.
2. Cylinder head for cracks, especially between valve
seats and in the exhaust ports.
3. Cylinder head deck for corrosion, sand particles in
head and porosity.
CAUTION:
Do not attempt to weld the cylinder head. Replace it.
4. Cylinder head deck, intake and exhaust manifold
mating surfaces for flatness.
These surfaces may be re-conditioned by milling. If
the surfaces are Òout of flatÓ by more than specifica-
tion, the surface should be grinded to within specifi-
cations. If more than limit of specification, it should
be replaced.
5. Water jacket sealing plugs seating surfaces.
6. Use a straight edge and a feeler gauge to measure
the manifold cylinder head fifting face warpage.
Regrind the exhaust manifold cylinder head fifting
surfaces if the measured values are between the
specified limit and the standard.
If the measured values exceed the specified limit, the
manifold must be replaced.
Cylinder Head
Lower Face
Warpagemm (in)
0.05 (0.0020)
or less0.20 (0.0079)
Cylinder Head
Height92 (3.6220)
–
Standard Limit
Standard Limit
mm(in)
0.05 (0.0020) or less 0.20 (0.0079) Exhaust Manifold Warpage

6A Ð 8 ENGINE MECHANICAL
At installed
height 38.9mm
(1.5in)StandardN(Kg/lb)
Limit
294.0 (30/66.1)257.9 (26.3/57.9)
Valve spring
CAUTION:
Visually inspect the valve springs and replace them if
damage or abnormal wear is evident.
1. Free height
·Measure the free height of the springs. The springs
must be replaced if the height is below the specified
limit.
INSPECTION AND REPAIR
Make the necessary adjustments, repairs, and part replacements if excessive wear or damage is discovered
during inspection.
2. Squareness
·Measure the valve spring squareness with a steel
square.
·Replace the valve springs if the measured value
exceeds the specified limit.
3. Spring tension
·Use a spring tester to compress the springs to the
installed height. Measure the compressed spring
tension.
Replace the springs if the measured tension is
below the specified limit.
Valve Guide
CAUTION:
Taking care not to damage the valve seat contact surface,
when removing carbon adhering to the valve head.
Carefully inspect the valve stem for scratching or
abnormal wear. If these conditions are present, the valve
and the valve guide must be replaced as a set.
Limitmm(in)
1.7 (0.0669)
Standard Limit
48.0 (1.8898) 47.100 (1.8543)mm(in)