jacking ISUZU TROOPER 1995 Workshop Manual

GENERAL INFORMATION OA-7
LIFTING INSTRUCTIONS
w CAUTION:
• • If a lifting device other than the original jack is used, it is most important that the device be applied only to
the correct lifting points. Raising the vehicle
from any other point may result in serious damage.
• When jacking or lifting a vehicle at the frame side rail or other prescribed lift points, be certain that lift pads
do not contact the catalytic converter, brake pipes or cables, or fuel lines. Such contact may result in dam­
age
or unsatisfactory vehicle performance.
LIFTING POINTS AND SUPPORTABLE POINT LOCATIONS
Long Wheel Base Model
Short Wheel Base Model
-Lifting point
~ Supportable point
·~ Fig.OA-5

REAR AXLE 48-3
DIAGNOSIS OF REAR AXLE NOISE
Many noises that seem to come from the rear axle
actually
originate from other sources such as tires,
road surface, wheel bearings, engine, transmission,
muffler,
or body drumming. Investigate to find the
source
ofthe noise before disassembling the rear axle.
Rear axles,
like any other mechanical device, are not
absolutely quiet but should be considered quiet unless
some abnormal noise is present.
To make a systematic check
for axle noise, observe the
following:
1. Select a level asphalt road to reduce tire noise and
body drumming.
2. Check rear axle lubricant level to assure correct
level, and then drive the vehicle far enough to
thoroughly warm up the rear axle lubricant.
3. Note the speed at which noise occurs. Stop the
vehicle and put the transmission in neutral. Run
the engine speed
slowly up and down to
determine if the noise is caused by exhaust,
muffler noise, or other engine conditions.
4. Tire noise changes with different road surfaces;
axle noises do not. Temporarily inflate all tires to
344
kPa (50 psi) (for test purposes only). This will
change noise caused by tires but will not affect
noise caused by the rear
axle.
Rear axle nose usually stops when coasting at
speeds under
48 km/h (30 mph); however, tire
noise continues
with a lower tone. Rear axle noise
usually changes when comparing pull and coast,
but tire noise stays about the same.
Distinguish between tire noise and rear
axle noise
by noting
if the noise changes with various
speeds
or sudden acceleration and deceleration.
Exhaust and
axle noise vary under these
conditions,
while tire noise remains constant and
is more pronounced at speeds
of 32 to 48 km/h
(20 to 30 mph). Further check for tire noise by
driving the vehicle
over smooth pavements or dirt
roads (not gravel) with the tires at normal
pressure.
If the noise is caused by tires, it will
change noticeably with changes in road surface.
5. Loose or rough front wheel bearings will cause
noise
which may be confused with rear axle
noise; however, front wheel bearing noise does
not change when comparing drive and coast.
Light application
of the brake while holding
vehicle speed steady
will often cause wheel
bearing noise to diminish. Front wheel bearings
may be checked for noise by jacking up the
wheels and spinning them
or by shaking the
wheels
to determine if bearings are loose.
6. Rear suspension rubber bushings and spring
insulators dampen
out rear axle noise when
correctly installed. Check to see that there is no
link or rod loosened or metal-to-metal contact.
7. Make sure that there is no metal-to-metal contact
between the
floor and the frame.
After the noise has been determined to be in the axle,
the type of axle noise should be determined, in order to
make any necessary repairs.
GEAR NOISE
Gear noise (whine) is audible from 32 to 89 km/h (20 to
55 mph) under four driving conditions.
1. In drive under acceleration or heavy pull.
2. Driving under load or under constant speed.
3. When using enough throttle to keep the vehicle
from driving the engine while the vehicle slows
down gradually (engine still pulls slightly).
4. When coasting with the vehicle in gear and the
throttle closed. The gear noise is
usually more
noticeable between 48 and 64
km/h (30 and 40
mph) and 80 and 89 km/h (50 and 55 mph).
BEARING NOISE
Bad bearings generally produce a rough growl or
grating sound, rather than the whine typical of gear
noise. Bearing noise frequently
"wow-wows" at
bearing rpm, indicating a bad pinion
or rear axle side
bearing. This noise can
be confused with rear wheel
bearing noise.
REAR WHEEL BEARING NOISE
Rear wheel bearing noise continues to be heard while
coasting at low speed with transmission in the neutral.
Noise may diminish by gentle braking. Jack up the rear
wheels, spin them by hand and
listen for noise at the
hubs. Replace any faulty
wheel bearings.
KNOCK AT LOW SPEEDS
Low speed knock can be caused by worn universal
joints or a side gear hub counter bore in the cage that is
worn oversize. Inspect and replace universal joints or
cage and side gears as required.
BACKLASH CLUNK
Excessive clunk on acceleration and deceleration can
be caused by a worn rear axle pinion shaft, a worn
cage, excessive clearance between the axle and the
side gear splines, excessive clearance between the
side gear hub and the counterbore in the cage,
worn
pinion and side gear teeth, worn thrust washers, or
excessive drive pinion and ring gear backlash.
Remove
worn parts and replace as required. Select
close-fitting parts when possible. Adjust pinion and
ring gear backlash.

6-2 ENGINE DIAGNOSIS
SECTION 6E-DRIVEABILITY
AND EMISSIONS
This section covers emission control systems general
information, and diagnostic procedures which will lead
to repairing performance and driveability related
problems.
Emission components are covered, as well
as removal and replacement procedures.
Instructions on use
of special tools are also given.
SECTION 6F-ENGINE EXHAUST
This section has information on all exhaust system
parts, such
as tailpipes, mufflers, and the catalytic
converter.
GENERAL DESCRIPTION
ENGINE CLEANLINESS AND CARE
An automobile engine is a combination of many
machined, honed,
polished and lapped surfaces with
tolerances that are measured in the thousandths of a
millimeter (ten thousandths of an inch). Accordingly,
when any
internal engine parts are serviced, care and
cleanliness are important. Throughout this section, it
should be understood that proper cleaning and
protection
of machined surfaces and friction areas is
part
of the repair procedure. This is considered
standard shop practice even
if not specifically stated.
• A liberal coating of engine oil should be applied to
all friction areas during assembly to protect and
lubricate the surfaces on initial operation.
• Whenever valve train components, pistons, piston
rings, connecting rods, rod bearings, and
crankshaft
journal bearings are removed for
service, they should be retained in order.
• At the time of installation, they should be installed
in the same locations and with the same mating
surfaces
as when removed.
• Battery cables should be disconnected before any
major
work is performed on the engine. Failure to
disconnect
cables may result in damage to wire
harness
or other electrical parts.
• The six cylinders of this engine are identified by
numbers; Right side
cylinders 1, 3 and 5, Left side
cylinders 2, 4 and 6, as counted from crankshaft
pulley side to flywheel side.
GENERAL INFORMATION ON ENGINE
SERVICE
The following information on engine service should be
noted
carefully, as it is important in preventing damage
and contributing
to reliable engine performance.
• When raising or supporting the engine for any
reason,
do not use a jack under the oil pan. Due to
the
small clearance between the oil pan and the oil
pump strainer, jacking against the oil pan may
cause damage to the
oil pick-up unit.
• The 12-volt electrical system is capable of
damaging circuits. When performing any work
where electrical terminals could possibly be
grounded, the ground cable of the battery should
be disconnected at the battery.
• Any time the intake air duct or air cleaner is
removed, the intake opening
should be covered.
This
will protect against accidental entrance of
foreign material into the cylinder which could
cause extensive damage when the engine is
started.
ENGINE DIAGNOSIS
CONTENTS
Hard Starting . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Engine Compression
Test Procedure ..... 6-4
Rough Engine
Idling or Engine Stalling . . . 6-5
Rough Engine Running . . . . . . . . . . . . . . . . .
6-6
Hesitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Engine Lacks
Power . . . . . . . . . . . . . . . . . . . . 6-8
Engine
Noisy .......................... 6-10
Abnormal Combustion . . . . . . . . . . . . . . . . . . 6-12
Engine Oil Consumption Excessive . . . . . . . 6-13
Fuel Consumption Excessive ............. 6-14
Oil Problems . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Malfunction Indicator Lamp . . . . . . . . . . . . . . 6-15
Engine Oil Pressure Check ............... 6-16
Inspection of Hydraulic Lash Adjuster . . . . . 6-17