oil pressure ISUZU AXIOM 2002 Service Owner's Guide

5C±63 POWER±ASSISTED BRAKE SYSTEM
The master cylinder contains two pistons that supply the
hydraulic pressure for a dual±circuit braking system. The
primary piston provides the fluid pressure to the front
brakes, while the secondary piston provides the fluid
pressure to the rear brakes. If the pressure is lost from
either system, the remaining system will function to stop
the vehicle.CAUTION:
1. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system. (Refer to
Bleeding Brake
Hydraulic System
in this section.)
2. The torque values specified are for dry,
unlubricated fasteners.
3. Perform service operations on a clean bench free
from all mineral oil materials.
Brake Booster
331R200001
This booster is a tandem vacuum unit with a diaphragm
effective diameter 205mm + 230mm (8.07in + 9.06in). In
normal operating mode, with the service brakes in the
released position, the tandem vacuum booster operates
with vacuum on both sides of its diaphragms. When the
brakes are applied, air at atmospheric pressure is
admitted to both sides of the diaphragm to provide the
power assist. When the service brake is released, the
atmospheric air is shut off from both sides of the
diaphram. The air is then drawn from the booster through
the vacuum check valve to the vacuum source.CAUTION:
1. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or
part of the brake system.
2. The torque values specified are for dry,
unlubricated fasteners.
3. The vacuum booster is not repairable and must be
replaced as complete assembly.

5C±64
POWER±ASSISTED BRAKE SYSTEM
Disc Brake
Front Disc Brake
A05R200001
Rear Disc Brake (4y4 Model)
A05RW002
The disc brake assembly consists of a caliper, piston,
rotor, pad assembly and support bracket. The caliper
assembly has a fornt dual bore, rear single bore and is
mounted to the support bracket with two mounting bolts.
The support bracket allows the caliper to move laterally
against the rotor. The caliper is a one±piece casting with
the inboard side containing the piston bore. A square cut
rubber seal is located in a groove in the piston bore which
provides the hydraulic seal between the piston and the
cylinder wall.
NOTE:
1. Replace all components included in repair kits used to
service this caliper.
2. Lubricate rubber parts with clean brake fluid to ease
assembly.3. If any hydraulic component is removed or
disconnected, it may be necessary to bleed all or part
of the brake system.
4. Replace pads in axle sets only.
5. The torque values specified are for dry, unlubricated
fasteners.
6. Perform the service operation on a clean bench free
from all mineral oil materials.
Operation
Hydraulic pressure, created by applying the brake pedal,
is converted by the caliper to a stopping force. This force
creates a clamping action of the piston pressing towards
the rotors (outward) and the caliper slides inward toward
the vehicle. This clamping action forces the linings
against the rotor, creating friction to stop the vehicle.

5C±67 POWER±ASSISTED BRAKE SYSTEM
General Diagnosis
ConditionPossible causeCorrection
Brake PullTire inflation pressure is unequal.Adjust
Front wheel alignment is incorrect.Adjust
Unmatched tires on same axle.Tires with approx. the same amount
of tread should be used on the same
axle.
Restricted brake pipes or hoses.Check for soft hoses and damaged
lines. Replace with new hoses and
new double walled steel brake
piping.
Water or oil on the brake pads.Clean or replace.
Brake pads hardened.Replace
Brake pads worn excessively.Replace
Brake rotor worn or scored.Grind or replace.
Disc brake caliper malfunctioning.Clean or replace.
Front hub bearing preload incorrect.Adjust or replace.
Loose suspension parts.Check all suspension mountings.
Loose calipers.Check and tighten the bolts to
specifications.
Brake Roughness or Chatter
(Pulsates)Excessive lateral runout.Check per instructions. If not within
specifications, replace or machine
the rotor.
Parallelism not within specifications.Check per instructions. If not within
specifications, replace or machine
the rotor.
Pad reversed (steel against iron).Replace the brake pad and machine
rotor to within specifications.
Excessive Pedal EffortMalfunctioning vacuum booster.Check the vacuum booster operation
and repair, if necessary.
Partial system failure.Check the front and rear brake
system for failure and repair. Also,
check the brake warning light. If a
failed system is found, the light
should indicate failure.
Excessively worn pad.Check and replace pads in sets.
Piston in caliper stuck or sluggish.Remove caliper and rebuild.
Fading brakes due to incorrect pad.Remove and replace with original
equipment pad or equivalent.
Vacuum leak to vacuum booster.Check for ruptured or loose hose.
Check the direction of check valve
within vacuum hose.Correct vacuum hose direction.
Grease on the brake pads.Replace or clean.
Excessive Brake Pedal TravelAir in hydraulic circuit.Bleed the hydraulic circuit.
Level of brake fluid in the reservoir
too low.Replenish brake fluid reservoir to
specified level and bleed hydraulic
circuit as necessary.
Master cylinder push rod clearance
excessive.Adjust
Leakage in hydraulic system.Correct or replace defective parts.

5C±70
POWER±ASSISTED BRAKE SYSTEM
Hydraulic Brakes
Filling Master Cylinder Reservoir
CAUTION: Use only specified brake fluid. Do not
use any fluid which contains a petroleum base. Do
not use a container which has been used for
petroleum based fluids or a container which is wet
with water. Petroleum based fluid will cause swelling
and distortion of rubber parts in the hydraulic brake
system. Water mixed with brake fluid lowers the fluid
boiling point. Keep all fluid containers capped to
prevent contamination.
Always fill the master cylinder reservoir when the en-
gine is cold.
Never allow the brake fluid to come in contact with
the painted surfaces.
The master cylinder reservoir must be kept properly
filled to ensure adequate reserve and to prevent air
and moisture from entering the hydraulic system.
However, because of expansion due to heat ab-
sorbed from the brakes and the engine, the reservoir
must not be overfilled. The brake fluid reservoir is on
the master cylinder, which is located under the hood
on the left side of the cowl. Thoroughly clean reser-
voir cap before removal to avoid getting dirt into res-
ervoir. Remove the diaphragm. Add fluid as required
to bring level to the ªMAXº mark on the reservoir
tank. Use ªDOT 3º Hydraulic Brake Fluid. If the fluid
cap diaphragm is stretched, return it to the original
position before installing.
Deterioration of Brake Fluid
Using any other brake fluid than specified or brake fluid
with mineral oil or water mixed in will drop the boiling point
of brake fluid. It may, in turn, result in vapor lock or
deteriorated rubber parts of the hydraulic system. Be sure
to change the brake fluid at specified intervals.
If the rubber parts are deteriorated, remove all the system
parts and clean them with alcohol. Prior to reassembly,
dry the cleaned parts with air to remove the alcohol.
Replace all the hoses and rubber parts of the system.
Leakage of Brake Fluid
With engine idling, set shift lever in the neutral position
and continue to depress brake pedal at a constant pedal
application force.
Should the pedal stroke become deeper gradually,
leakage from the hydraulic pressure system is possible.
Perform visual inspection for any signs of leakage.
Bleeding Brake Hydraulic System
A bleeding operation is necessary to remove air from the
hydraulic brake system whenever air is introduced into
the hydraulic system. It may be necessary to bleed the
hydraulic system at all four brakes if air has been
introduced through a low fluid level or by disconnecting
brake pipes at the master cylinder. If a brake pipe is
disconnected at one wheel, only that wheel
cylinder/caliper needs to be bled. If the pipes are
disconnected at any fitting located between the master
cylinder and brakes, then the brake system served by the
disconnected pipe must be bled.
1. For 4±Wheel Antilock Brake System (ABS) equipped
vehicle, be sure to remove the ABS main fuse 60A
located at the relay and fuse box before bleeding air. If
you attempt to bleed air without removing the main
fuse, air cannot be let out thoroughly, and this may
cause damage to the hydraulic unit. After bleeding air,
be sure to replace the ABS main fuse back to its
original position.
2. Set the parking brake completely, then start the
engine.
NOTE: The vacuum booster will be damaged if the
bleeding operation is performed with the engine off.
3. Remove the master cylinder reservoir cap.
4. Fill the master cylinder reservoir with brake fluid.
Keep the reservoir at least half full during the air
bleeding operation
5. Always use new brake fluid for replenishment.
6. When replenishing the brake fluid reservoir, carefully
pour in the brake fluid to prevent air bubbles from
entering the brake system.
When the master cylinder is replaced or overhauled,
first bleed the air from the master cylinder, then from
each wheel cylinder and caliper following the
procedures described below.
Bleeding the Master Cylinder
7. Disconnect the rear wheel brake pipe (1) from the
master cylinder.
Check the fluid level and replenish as necessary. If
replenished, leave the system for at least one minute.
8. Depress the brake pedal slowly once and hold it
depressed.
9. Completely seal the delivery port of the master
cylinder with your finger, where the pipe was
disconnected then release the brake pedal slowly.
10. Release your finger from the delivery port when the
brake pedal returns completely.
11. Repeat steps 8 through 10 until the brake fluid comes
out of the delivery port during step 8.

6A±3
ENGINE MECHANICAL (6VE1 3.5L)
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.
Cylinder Block
The cylinder block is made of aluminum die±cast casting
for 75
V±type six cylinders. It has a rear plate integrated
structure and employs a deep skirt. The cylinder liner is
cast and the liner inner diameter and crankshaft journal
diameter are classified into grades. The crankshaft is
supported by four bearings of which width is different
between No.2, No.3 and No.1, No.4; the width of No.3
bearing on the body side is different in order to support the
thrust bearing. The bearing cap is made of nodular cast
iron and each bearing cap uses four bolts and two side
bolts.
Cylinder Head
The cylinder head, made of aluminum alloy casting
employs a pent±roof type combustion chamber with a
spark plug in the center. The intake and exhaust valves
are placed in V±type design. The ports are cross±flow
type.
Valve Train
Intake and exhaust camshaft on both banks are driven
with a camshaft drive gear by the timing belt. The valves
are operated by the camshaft and the valve clearance is
adjusted to select suitable thickness shim.
Intake Manifold
The intake manifold system is composed of the aluminum
cast common chamber and intake manifold attached with
six fuel injectors.
Exhaust Manifold
The exhaust manifold is made of nodular cast iron.
Pistons and Connecting Rods
Aluminum pistons are used after selecting the grade that
meets the cylinder bore diameter. Each piston has two
compression rings and one oil ring. The piston pin made
of chromium steel is offset 1mm toward the thrust side,
and the thrust pressure of piston to the cylinder wall varies
gradually as the piston travels. The connecting rods are
made of forged steel. The connecting rod bearings are
graded for correct size selection.
Crankshaft and Bearings
The crankshaft is made of Ductile cast±iron. Pins and
journals are graded for correct size selection for their
bearing.

6A±5
ENGINE MECHANICAL (6VE1 3.5L)
4. Engine Lacks Compression
Condition
Possible causeCorrection
Engine lacks compressionSpark plug loosely fitted or spark
plug gasket defectiveTighten to specified torque or replace
gasket
Valve timing incorrectAdjust
Cylinder head gasket defectiveReplace gasket
Valve incorrectly seatedLap valve
Valve stem seizedReplace valve and valve guide
Valve spring weakened or brokenReplace
Cylinder or piston rings wornOverhaul engine
Piston ring seizedOverhaul engine.
Engine Compression Test Procedure
1. Start and run the engine until the engine reaches
normal operating temperature.
2. Turn the engine off.
3. Remove all the spark plugs.
4. Remove ignition coil fuse (15A) and disable the
ignition system.
5. Remove the fuel pump relay from the relay and fuse
box.
6. Engage the starter and check that the cranking speed
is approximately 300 rpm.
7. Install cylinder compression gauge into spark plug
hole.
8. With the throttle valve opened fully, keep the starter
engaged until the compression gage needle reaches
the maximum level. Note the reading.
9. Repeat the test with each cylinder.
If the compression pressure obtained falls below the
limit, engine overhaul is necessary.
Limit; 1000 kPa (145 psi)

6A±7
ENGINE MECHANICAL (6VE1 3.5L)
Rough Engine Running
ConditionPossible causeCorrection
Engine misfires periodicallyIgnition coil layer shortedReplace
Spark plugs foulingClean or install hotter type plug
Spark plug(s) insulator nose leakingReplace
Fuel injector(s) defectiveReplace
Powertrain control module faultyReplace
Engine knocks periodicallySpark plugs running too hotInstall colder type spark plugs
Powertrain control module faultyReplace
Ion Sensing module faultyRefer or replace
Engine lacks powerSpark plugs fouledClean
Fuel injectors defectiveReplace
Mass Airflow Sensor or Intake
Airflow Sensor circuit defectiveCorrect or replace
Manifold Absolute Pressure (MAP)
Sensor or Manifold Absolute
Pressure Sensor circuit defectiveCorrect or replace
Engine Coolant Temperature Sensor
or Engine Coolant Temperature
Sensor circuit defectiveCorrect or replace
Powertrain Control Module faultyReplace
Intake Air Temperature Sensor or
Intake Air Temperature Sensor
circuit defectiveCorrect or replace
Throttle Position Sensor or Throttle
Position Sensor circuit defectiveCorrect or replace
ION Sensing Module or ION Sensing
Module circuits defectiveCorrect or replace

6A±10
ENGINE MECHANICAL (6VE1 3.5L)
Engine Lacks Power
ConditionPossible causeCorrection
Trouble in fuel systemFuel Pressure Control Valve not
working normallyReplace
Fuel injector cloggedClean or replace
Fuel pipe cloggedClean
Fuel filter clogged or fouledReplace
Fuel pump drive circuit not working
normallyCorrect or replace
Fuel tank not sufficiently breathing
due to clogged Evaporative
Emission Control System circuitClean or replace
Water in fuel systemClean
Inferior quality fuel in fuel systemUse fuel of specified octane rating
Powertrain Control Module supplied
poor voltageCorrect circuit
Throttle Position Sensor cable
broken or poor connectionsCorrect or replace
Throttle Position Sensor defectiveReplace
Mass Airflow Sensor not working
normallyReplace
Manifold Absolute Pressure Sensor
not working normallyReplace
Intake Air Temperature Sensor not
working normallyReplace
Engine Coolant Temperature Sensor
circuit open or shortedCorrect or replace
Engine Coolant Temperature Sensor
defectiveReplace
Powertrain Control Module defectiveReplace
Trouble in intake or exhaust systemAir Cleaner Filter cloggedReplace filter element
Air duct kinked or flattenedCorrect or replace
TWC defectiveRepair
Ignition failureÐÐÐÐRefer to Hard Start Troubleshooting
Guide
Heat range of spark plug inadequateInstall spark plugs of adequate heat
range
Ignition coil defectiveReplace

6A±11
ENGINE MECHANICAL (6VE1 3.5L)
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

6A±16
ENGINE MECHANICAL (6VE1 3.5L)
Engine Oil Consumption Excessive
ConditionPossible causeCorrection
Oil leakingOil pan drain plug looseRetighten or replace gasket
Crankcase fixing bolts loosenedRetighten
Oil pan setting bolts loosenedRetighten
Oil pan gasket brokenReplace gasket
Front cover retaining bolts loose or
gasket brokenRetighten or replace gasket
Head cover fixing bolts loose or
gasket brokenRetighten or replace gasket
Oil filter adapter crackedReplace
Oil filter attachings bolt loose or
rubber gasket brokenRetighten or replace oil filter
Crankshaft front or rear oil seal
defectiveReplace oil seal
Oil pressure unit loose or brokenRetighten or replace
Blow±by gas hose brokenReplace hose
Positive Crankcase Ventilation Valve
cloggedClean
Engine/Transmission coupling failedReplace oil seal
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