oil viscosity ISUZU TROOPER 1998 Service Repair Manual

MAINTENANCE AND LUBRICATION 0BÐ1
SECTION 0B
MAINTENANCE AND LUBRICATION
CONTENTS
PAGE
Maintenance Schedule...................................................0BÐ 2
Recommended Fluids, Lubricants and Fuels.................................0BÐ 7
Oil Viscosity Chart.......................................................0BÐ10
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFER
TO THE SRS SERVICE INFORMATION. FAILURE
TO FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS
SYSTEM REPAIRS.CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, or
other corrosion inhibitors) on threaded fasteners
or fasteners joint interfaces. Generally, such
coatings adversely affect the fastener torque and
the joint clamping force, and may damage the
fastener. When you install fasteners, use the
correct tightening sequence and specification.
Following these instructions can help you avoid
damage to parts and systems.

0BÐ10 MAINTENANCE AND LUBRICATION
OIL VISCOSITY CHART
Lubricants should be carefully selected according to the lubrication chart. It is also important to select
viscosity of lubricants according to the ambient temperature by referring to the following table.
OIL VISCOSITY CHART FOR GASOLINE ENGINE
APPLY GASOLINE ENGINE OIL
SAE 30
SAE 5W-30
SAE 15W-40,20W-40,20W-50
SAE 10W-30
SAE 20,20W
SAE 10W
EG-01 (Multi grade) (Single grade)VISCOSITY GRADE - AMBIENT TEMPERATURE
µ25˚C
µ13˚Fµ15˚C
˚F˚C
˚F ˚C
˚F ˚C
˚F
OIL VISCOSITY CHART FOR DIESEL ENGINE
APPLY DIESEL ENGINE OIL
VISCOSITY GRADE - AMBIENT TEMPERATURE
Multi grade

SAE 5W-30
SAE 10W-30
–25¡C –15¡C0¡C –10¡C15¡C25¡C30¡C
–13¡F5¡F32¡F 14¡F60¡F77¡F86¡F
905RW017

MAINTENANCE AND LUBRICATION 0BÐ11
OIL VISCOSITY CHART FOR MANUAL TRANSMISSION AND TRANSFER CASE
APPLY ENGINE OIL
SAE 5W-30
SAE 15W-40,20W-40,20W-50
SAE 10W-30
SAE 40,50
ET-12 (Multi-grade) (Single grade)VISCOSITY GRADE - AMBIENT TEMPERATURE
SAE 30
µ25˚C
µ13˚Fµ10˚C
˚F˚C
˚F ˚C
˚F ˚C
˚F˚C
˚F
OIL VISCOSITY CHART FOR FRONT AXLE (Manual and Auto locking hub model)
AND REAR AXLE
APPLY GEAR OIL
SAE 75W-90
SAE 80W-140
SAE 80W-90
GA-06 (Multi grade)(Single grade)GEAR OIL VISCOSITY GRADE - AMBIENT TEMPERATURE
µ25˚C
µ13˚F˚C
˚F µ10˚C
˚F˚C
˚F ˚C
˚F ˚C
˚F
SAE 80W
SAE 75W
SAE 140
SAE 90

0BÐ12 MAINTENANCE AND LUBRICATION
OIL VISCOSITY CHART FOR FRONT AXLE (Shift on the fly model)
APPLY GEAR OIL
GEAR OIL VISCOSITY GRADE – AMBIENT TEMPERATURE
(Multi grade)
SAE 80W – 90, 80W – 140
SAE 75W – 90
–25¡C
–13¡F14¡F32¡F59¡F86¡F95¡F –10¡C15¡C30¡C35¡C 0¡C

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

1D Ð 24 COMPRESSOR OVERHAUL
6. Remove any excess oil resulting from installing the
new seal parts from the shaft and inside the
compressor neck.
7. Install the clutch plate and hub assembly as
described previously.8. Reinstall compressor belt and tighten bracket.
9. Evacuate and charge the refrigerant system.
COMPRESSOR PRESSURE RELIEF VALVE
Removal
1. Recover the refrigerant using Refrigerant Recovery
System.
2. Remove old pressure relief valve.
Installation
1. Clean valve seat area on rear head.2. Lubricate O-ring of new pressure relief valve and
O-ring assembly with new 525 viscosity refrigerant
oil. Install new valve and torque in place, 9.0 Nám
(6.1 ft lbs)
3. Evacuate and recharge the system.
4. Leak test system.
COMPRESSOR OIL
Compressor Oil Check
The oil used to lubricate the compressor is circulating
with the refrigerant.
Whenever replacing any component of the system or a
large amount of gas leakage occurs, add oil to maintain
the original amount of oil.
Checking and Adjusting Oil Quantity for
Used Compressor
1. Perform oil return operation. Refer to Oil Return
Operation in this section.
2. Discharge and recover refrigerant and remove the
compressor.
3. Drain the compressor oil and measure the extracted
oil with a measuring cylinder.
4. If the amount of oil drained is much less than 90 cc
(3.0 fl. oz.), some refrigerant may have leaked out.
Conduct a leak tests on the connections of each
system, and if necessary, repair or replace faulty
parts.
5. Check the compressor oil contamination. (Refer to
Contamination of Compressor Oil in this section.)
6. Adjust the oil level following the next procedure
below.7. Install the compressor, then evacuate, charge and
perform the oil return operation.
8. Check system operation.
When it is impossible to preform oil return
operation, the compressor oil should be checked in
the following order:
1. Discharge and recover refrigerant and remove the
compressor.
2. Drain the compressor oil and measure the extracted
oil with a measuring cylinder.
3. Check the oil for contamination.
4. If more than 90 cc (3.0 fl. oz.) of oil is extracted from
the compressor, supply the same amount of oil to
the compressor to be installed. If the amount of oil
extracted is less than 90 cc (3.0 fl. oz.), recheck the
compressor oil in the following order:
5. Supply 90 cc (3.0 fl. oz.) of oil to the compressor
and install it onto the vehicle.
6. Evacuate and recharge with the proper amount of
refrigerant.
7. Perform the oil return operation.
8. Remove the compressor and recheck the amount of
oil.
9. Adjust the compressor oil, if necessary.
Checking and Adjusting for Compressor
Replacement
The oil is not charged in compressor (service parts). So
it is necessary to charge the proper amount of oil to the
new compressor. (Oil Capacity)
Capacity total in system 150 cc (5.0 fl.oz)
Compressor (Service 150 cc (5.0 fl.oz)
parts) charging amount
(Collected Amount) (Charging Amount)
more than 90 cc same as collected
(3.0 fl.oz) amount
less than 90 cc (3.0 fl.oz) 90 cc (3.0 fl.oz)
(Collected Amount) (Charging Amount)
more than 90 cc same as collected
(3.0 fl.oz) amount
less than 90 cc (3.0 fl.oz) 90 cc (3.0 fl.oz)

6A±15
ENGINE MECHANICAL
Condition CorrectionPossible cause
Oil leaking into combustion
chambers due topoor seal in valve
Valve stem oil seal defectiveReplace
chambers due to oor seal in valve
systemValve stem or valve guide wornReplace valve and valve guide
Oil leaking into combustion
chambers due to poor seal in cylinder
t
Cylinders and pistons worn
excessivelyReplace cylinder body assembly and
pistons
partsPiston ring gaps incorrectly
positionedCorrect
Piston rings set with wrong side upCorrect
Piston ring stickingReplace cylinder body assembly and
pistons
Piston ring and ring groove wornReplace pistons and others
Return ports in oil rings cloggedClean piston and replace rings
Positive Crankcase Ventilation
System malfunctioningPositive Crankcase Ventilation Valve
cloggedClean
OthersImproper oil viscosityUse oil of recommended S.A.E.
viscosity
Continuous high speed driving
and/or severe usage such as trailer
towingContinuous high speed operation
and/or severe usage will normally
cause increased oil consumption
Fuel Consumption Excessive
ConditionPossible causeCorrection
Trouble in fuel systemMixture too rich or too lean due to
trouble in fuel injection systemRefer to ªAbnormal Combustionº
Fuel cut function does not workRefer to ªAbnormal Combustionº
Trouble in ignition systemMisfiring or abnormal combustion
due to trouble in ignition systemRefer to ªHard Startº or ªAbnormal
Combustionº
OthersEngine idle speed too highReset Idle Air Control Valve
Returning of accelerator control
sluggishCorrect
Fuel system leakageCorrect or replace
Clutch slippingCorrect
Brake dragCorrect
Selection of transmission gear
incorrectCaution operator of incorrect gear
selection
Excessive Exhaust Gas
Recirculation flow due to trouble in
Exhaust Gas Recirculation systemRefer to ªAbnormal Combustionº

6A±16
ENGINE MECHANICAL
Lubrication Problems
ConditionPossible causeCorrection
Oil pressure too lowWrong oil in useReplace with correct engine oil
Relief valve stickingReplace
Oil pump not operating properlyCorrect or replace
Oil pump strainer cloggedClean or replace strainer
Oil pump wornReplace
Oil pressure gauge defectiveCorrect or replace
Crankshaft bearing or connecting
rod bearing wornReplace
Oil contaminationWrong oil in useReplace with correct engine oil
Oil filter cloggedReplace oil filter
Cylinder head gasket damageReplace gasket
Burned gases leakingReplace piston and piston rings or
cylinder body assembly
Oil not reaching valve systemOil passage in cylinder head or
cylinder body cloggedClean or correct
Engine Oil Pressure Check
1. Check for dirt, gasoline or water in the engine oil.
a. Check the viscosity of the oil.
b. Change the oil if the viscosity is outside the
specified standard.
c. Refer to the ªMaintenance and Lubricationº section
of this manual.
2. Check the engine oil level.
The level should fall somewhere between the ªADDº
and the ªFULLº marks on the oil level dipstick.
If the oil level does not reach the ªADDº mark on the
oil level dipstick, engine oil must be added.3. Remove the oil pressure unit.
4. Install an oil pressure gauge.
5. Start the engine and allow the engine to reach normal
operating temperature (About 80
C).
6. Measure the oil pressure.
Oil pressure should be:
392±550 kPa (56.9±80.4 psi) at 3000 rpm.
7. Stop the engine.
8. Remove the oil pressure gauge.
9. Install the oil pressure unit.
10. Start the engine and check for leaks.

6E±38
ENGINE DRIVEABILITY AND EMISSIONS
General Service Information
OBD Serviceablity Issues
The list of non-vehicle faults that could affect the
performance of the OBD system has been compiled.
These non-vehicle faults vary from environmental
conditions to the quality of fuel used.
The illumination of the MIL (ªCheck Engineº lamp) due to
a non-vehicle fault could lead to misdiagnosis of the
vehicle, increased warranty expense and customer
dissatisfaction. The following list of non-vehicle faults
does not include every possible fault and may not apply
equally to all product lines.
Fuel Quality
Using fuel with the wrong octane rating for your vehicle
may cause driveability problems. Many of the major fuel
companies advertise that using ªpremiumº gasoline will
improve the performance of your vehicle. Most premium
fuels use alcohol to increase the octane rating of the fuel.
Although alcohol-enhanced fuels may raise the octane
rating, the fuel's ability to turn into vapor in cold
temperatures deteriorates. This may affect the starting
ability and cold driveability of the engine.
Low fuel levels can lead to fuel starvation, lean engine
operation, and eventually engine misfire.
Non-OEM Parts
All of the OBD diagnostics have been calibrated to run
with OEM parts. Something as simple as a
high-performance exhaust system that affects exhaust
system back pressure could potentially interfere with the
operation of the EGR valve and thereby turn on the MIL
(ªCheck Engineº lamp). Small leaks in the exhaust
system near the post catalyst oxygen sensor can also
cause the MIL (ªCheck Engineº lamp) to turn on.
Aftermarket electronics, such as cellular phones,
stereos, and anti-theft devices, may radiate EMI into the
control system if they are improperly installed. This may
cause a false sensor reading and turn on the MIL (ªCheck
Engineº lamp).
Environment
Temporary environmental conditions, such as localized
flooding, will have an effect on the vehicle ignition system.
If the ignition system is rain-soaked, it can temporarily
cause engine misfire and turn on the MIL (ªCheck Engineº
lamp).
Poor Vehicle Maintenance
The sensitivity of OBD diagnostics will cause the MIL
(ªCheck Engineº lamp) to turn on if the vehicle is not
maintained properly. Restricted air filters, fuel filters, and
crankcase deposits due to lack of oil changes or improper
oil viscosity can trigger actual vehicle faults that were not
previously monitored prior to OBD. Poor vehicle
maintenance can not be classified as a ªnon-vehicle
faultº, but with the sensitivity of OBD diagnostics, vehicle
maintenance schedules must be more closely followed.Related System Faults
Many of the OBD system diagnostics will not run if the
PCM detects a fault on a related system or component.
One example would be that if the PCM detected a Misfire
fault, the diagnostics on the catalytic converter would be
suspended until Misfire fault was repaired. If the Misfire
fault was severe enough, the catalytic converter could be
damaged due to overheating and would never set a
Catalyst DTC until the Misfire fault was repaired and the
Catalyst diagnostic was allowed to run to completion. If
this happens, the customer may have to make two trips to
the dealership in order to repair the vehicle.
Maintenance Schedule
Refer to the Maintenance Schedule.
Visual / Physical Engine Compartment
Inspection
Perform a careful visual and physical engine
compartment inspection when performing any diagnostic
procedure or diagnosing the cause of an emission test
failure. This can often lead to repairing a problem without
further steps. Use the following guidelines when
performing a visual/physical inspection:

Inspect all vacuum hoses for punches, cuts,
disconnects, and correct routing.

Inspect hoses that are difficult to see behind other
components.

Inspect all wires in the engine compartment for proper
connections, burned or chafed spots, pinched wires,
contact with sharp edges or contact with hot exhaust
manifolds or pipes.
Basic Knowledge of Tools Required
NOTE: Lack of basic knowledge of this powertrain when
performing diagnostic procedures could result in an
incorrect diagnosis or damage to powertrain
components. Do not attempt to diagnose a powertrain
problem without this basic knowledge.
A basic understanding of hand tools is necessary to effec-
tively use this section of the Service Manual.
Serial Data Communications
Class II Serial Data Communications
This vehicle utilizes the ªClass IIº communication system.
Each bit of information can have one of two lengths: long
or short. This allows vehicle wiring to be reduced by
transmitting and receiving multiple signals over a single
wire. The messages carried on Class II data streams are
also prioritized. If two messages attempt to establish
communications on the data line at the same time, only
the message with higher priority will continue. The device
with the lower priority message must wait. The most
significant result of this regulation is that it provides Tech 2
manufacturers with the capability to access data from any
make or model vehicle that is sold.

SERVICE INFORMATION 00 Ð 11
8. DARK EXHAUST SMOKE
Checkpoint Possible cause Correction
Air cleaner Clogged air cleaner element Clean or replace the air cleaner
element
Injection nozzle Injection nozzle injection starting pressure
too low
Improper spray conditionAdjust or replace the injection
nozzle
Fuel injection timing Fuel injection timing improperly adjusted Adjust the fuel injection timing
Injection pump Defective Delivery valve resulting is fuel
drippage after fuel injectionReplace the delivery valve
Excessive injection volume Adjust the injection volume
9. OIL PRESSURE DOES NOT RISE
Checkpoint Possible cause Correction
Engine oil Improper viscosity engine oil. Insufficient
engine oilReplace the engine oil
Correct the engine oil volume
Oil pressure gauge
or unit
Oil pressure indicator
lightDefective oil pressure gauge or unit
Defective indicator lightRepair or replace the oil pressure
gauge or unit
Replace the indicator light
Oil filter Clogged oil filter element Replace the oil filter element or the
oil filter cartridge
Relief valve and by-
pass valveRelief valve sticking and/or weak by-pass
valve springReplace the relief valve and/or the
by-pass valve spring
Oil pump Clogged oil pump strainer Clean the oil pump strainer
Worn oil pump related parts Replace the oil pump related parts
Rocker arm shaft Worn rocker arm bushing Replace the rocker arm bushing
Camshaft Worn camshaft and camshaft bearing Replace the camshaft and the
camshaft bearing
Crankshaft and
bearingsWorn crankshaft and bearings Replace the crankshaft and/or the
bearings