maintenance ISUZU TF SERIES 2004 Workshop Manual

5C-20 BRAKES







Operation

The operation of the P-valve by the master cylinde
r
pressure is unchanged up to the brake points
A and B.
If master cylinder fluid pressure penetrates into the second
break point
B, the fluid pressure pressing against the seal
2, (which isolated route 4 and route 5), passing the route
4of the master cylinder side, overcomes the operating
force of the spring
3 + fluid pressure affecting the seal 2of
the wheel cylinder, and presses the piston
1to the right
side, resulting in the opening of the routes
4 and 5, and
canceling of the P-valve operation.
Then, because the master cylinder fluid pressure and the
wheel cylinder fluid pressure, up to the point
C, operate on
the identical surface of the seal
2, both have identical
ascending ratio.
However, because of the operation of spring
3 in the wheel
cylinder side, wheel cylinder fluid pressure operate to
preserve the balance against the master cylinder fluid
pressure on the lower level with the difference in pressure
resulting from this spring.
03260002-2


Valve Maintenance
In the case of fluid leak or other abnormalities, faulty valve
should be replaced.
The valve is set up at the engine room.
Note:
The blend proportioning valve is not repairable and must
be replaced as a complete assembly.

BRAKES 5C-23

RTW35CSH001301

4) Failure on front master cylinder.
In case of failure on front master cylinder the pressure on
the inlet port (C) drop to zero. The pressure from inlet por
t
(A) acts on the bypass piston (2) and move it by comprising
of bypass spring (3). It makes possible the communication
between the inlet port (A) to outlet port (B) through the
bypass system. The outlet pressure (B) reaches the inle
t
pressure (A) and the LSPV is bypassed.


Valve Maintenance
In the case to fluid lead or other a abnormalities, faulty valve
should be replaced.
Note:
The load sensing proportioning valve is not repairable and
must be replaced as a completed assembly.


LOAD SENSING PROPORTIONING
VALVE (LSPV) ADJUSTMENT
RTW35CSH000301

1. Fluid Pressure Measurement
1) Rear axle weight adjustment
With an axle eight meter, adjust the rear axle weight with
a person sitting in the driver’s seat and a weight loaded
in the rear body.
N (kg/lb)

MODEL Adjustment value
4

2 7845 (800/1764)
4
2 HIGH RIDE
4

4 9316 (950/2095)

RTW35CSH000101





2) Installation of a fluid pressure gauge
Remove the air bleeder of the left hand wheel front and
rear brakes. Bleed air out of the fluid pressure gauge
with the measurement hose of the fluid pressure gauge
installed.
Pressure Tester: Brake oil (Fluid pressure gauge)
5-8840-2190-0

CLUTCH 7C-19
SERVICING
Servicing refers to general maintenance procedures to be performed by qualified service personnel.




CLUTCH PEDAL PLAY
Inspection
Depress the clutch pedal lightly by hand, and measure to
determine if the free play is within the standard value.
Pedal Free Play mm(in)
H 5.0-15.0 (0.2-0.6)



Adjustment of the clutch switch (or stopper bolt)
Turn the clutch switch or stopper bolt
1 until the switch bolt
or
stopper bolt
just touches the clutch pedal arm.
Adjust clutch switch
or stopper bolt
by backing it out half a turn,
and measure the clearance (L) between the clutch pedal arm
and the clutch switch bolt end
or stopper bolt.
Lock the lock nut

2.
Connect clutch switch connector.
Clutch switch and clutch pedal
Clearance mm(in)
(L) 0.5-1.5 (0.020-0.059)

6A – 24 ENGINE MECHANICAL

SERVICING
Servicing refers to general maintenance procedures to be performed by qualified service personnel.



RTW36ASH000401
MODEL IDENTIFICATION
Engine Serial Number
The engine number is stamped on the rear left hand side
of the cylinder body.
The engine number is stamped in the plate in front of the
engine room as well.


AIR CLEANER
Element cleaning procedures will vary according to the
condition of the element.

Dust Fouled Element
Rotate the element with your hand while applying
compressed air to the inside of the element. This will blow
the dust free.
Compressed air pressure kPa (kg/cm
2 /psi)
392 – 490 (4 – 5/57 – 71)


LUBRICATING SYSTEM
Main Oil Filter (Cartridge Type Paper Element)
Replacement Procedure
1. Drain the engine oil.
2. Retighten the drain plug.
3. Loosen the used oil filter by turning it counterclockwise
with a filter wrench.
Filter Wrench: 5-8840-0200-0


RTW36ASH000101


4. Clean the oil cooler fitting face. This will allow the new
oil filter to seat properly.
5. Apply a light coat of engine oil to the filter O-ring.
6. Turn in the new oil filter until the filter O-ring is fitted
against the sealing face.
7. Use the filter wrench to turn in the filter an additional
2/3 turns.
8. Check the engine oil level and replenish to the
specified level if required.
130RY00003
6A-6

ENGINE MECHANICAL 6A – 41

















































Coolant Replenishment
Warning:
When the coolant is heated to a high temperature, be
sure not to loosen or remove the rediator cap.
Otherwise you might get scalded by hot vapor or
boiling water.
To open the radiator cap, put a piece of thick cloth on
the cap and loosen the cap slowly to reduce the
pressure when the coolant has become cooler.
1. Open rediator cap pour coolant up to filler neck
2. Pour coolant into reservoir tank up to "MAX" line
3. Tighten radiator cap and start the engine. After idling
for 2 to 3 minutes, stop the engine and reopen radiator
cap. If the water level is lower, replenish.
4. After replenish the coolant tighten radiator cap, warm
up the engine at about 2000 rpm. Set heater
adjustment to the highest temperature position, and let
the coolant circulate also into heater water system.
5. Check to see the thermometer, continuously idling 5
minutes and stop the engine.
6. When the engine has been cooled, check filler neck for
water level and replenish if required. Should extreme
shortage of coolant is found, check the coolant system
and reservoir tank hose for leakage.
7. Pour coolant into the reservoir tank up to "MAX" line.

Coolant Capacity lit (US/UK gal)

4JA1 / TC 9.4 (2.5 / 2.1)
4JH1TC M/T: 10.1 (2.7 / 2.2)
A/T: 10.0 (2.6 / 2.2)

9.5 (2.5/2.1)
























Engine Warm-Up
After completing the required maintenance procedures,
start the engine and allow it to idle until it is warm.
Check the following:
1. Engine idling speed.
2. Engine noise level.
3. Engine lubricating system and cooling system.
Carefully check for oil and coolant leakage.
4. Clutch engagement.
5. Transmission operation.
6. Indicator warning light operation.

6D – 32 ENGINE ELECTRICAL


MAGNETIC SWITCH
The following tests must be performed with the starter
motor fully assembled.
The yoke lead wire must be disconnected from the “M”
terminal.
To prevent coil burning, complete each test as quickly as
possible (within three to five seconds).





RTW46DSH004601
Temporarily connect the solenoid switch between the
clutch and the housing and run the following test.
Complete each test within three to five seconds.
1. Pull-in Test
Connect the battery negative terminal with the solenoid
switch body and the M terminal. When current is applied to
the S terminal from the battery positive terminal, the pinion
should flutter.




RTW46DSH005901
2. Hold-in Maintenance Test
Disconnect the lead at the M terminal. The pinion should
continue to flutter.




RTW46DSH004701
3. Return Test
Disconnect the battery positive lead at the S terminal.
The pinion should return to its home position.

6E–82 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
GENERAL SERVICE INFORMATION
Serviceability Issues
Non-OEM Parts
All of the OBD diagnostics have been calibrated to run
with OEM parts. Accordingly, if commercially sold
sensor or switch is installed, it makes a wrong diagnosis
and turns on the check engine lamp.
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 check
engine lamp.
Poor Vehicle Maintenance
The sensitivity of OBD diagnostics will cause the check
engine lamp to turn on if the vehicle is not maintained
properly. Restricted oil 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 “non-vehicle
fault”, 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
ECM detects a fault on a related system or component.
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
effectively use this section of the Service Manual.
ON-BOARD DIAGNOSTIC (OBD)
On-Board Diagnostic (Self Diagnosis
System) Tests
A diagnostic test is a series of steps, the result of which
is a pass or fail reported to the diagnostic ex ecutive.
When a diagnostic test reports a pass result, the
diagnostic ex ecutive records the following data:
The diagnostic test has been completed since the
last ignition cycle.
The diagnostic test has passed during the current
ignition cycle.
The fault identified by the diagnostic test is not
currently active.
When a diagnostic test reports a fail result, the
diagnostic ex ecutive records the following data:
The diagnostic test has been completed since the
last ignition cycle.
The fault identified by the diagnostic test is currently
active.
The fault has been active during this ignition cycle.
The operating conditions at the time of the failure.
The Diagnostic Executive
The Diagnostic Executive is a unique segment of
software which is designed to coordinate and prioritize
the diagnostic procedures as well as define the protocol
for recording and displaying their results. The main
responsibilities of the Diagnostic Ex ecutive are listed as
follow s:
Commanding the check engine lamp on and off
DTC logging and clearing
Current status information on each diagnostic
Diagnostic Information
The diagnostic charts and functional checks are
designed to locate a faulty circuit or component through
a process of logical decisions. The charts are prepared
with the requirement that the vehicle functioned
correctly at the time of assembly and that there are not
multiple faults present.
There is a continuous self-diagnosis on certain control
functions. This diagnostic capability is complemented
by the diagnostic procedures contained in this manual.
The language of communicating the source of the
malfunction is a system of diagnostic trouble codes.
When a malfunction is detected by the control module, a
diagnostic trouble code is set and the check engine
lamp is illuminated.
Check Engine Lamp
The check engine lamp looks the same as the check
engine lamp you are already familiar with, the “Check
Engine” lamp.
Basically, the check engine lamp is turned on when the

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–181
5 V i s u a l l y / p h y s i c a l l y i n s p e c t f o r t h e f o l l o w i n g c o n d i t i o n s .
Restrict fuel supply system. Check for a pinched
fuel ho se /pi pe.
Check for a condition that causes fuel wax ing or
icing, such as the customer is using an incorrect
fuel type in winter season or water mix ed with the
f u e l.
If a problem is found, repair as necessary.
Was a problem found? - Verify repair Go to Step 6
6 Replace the fuel fi lt er.
Was the problem solved? - Verify repair Go to Step 7
7 Remove the eye bolt with gauze filter from the
injection pump and check for the following conditions.

Objects blocking at the gauze filter. Check for a
condition that causes contaminated fuel, such as
the customer is using an aftermarket fuel filter or
ex tended maintenance interval.
Check for a condition that causes fuel wax ing or
icing, such as the customer is using an incorrect
fuel type in winter season or water mix ed with the
f u e l.
If a problem is found, repair as necessary.
Was the problem found?
-Replace the
eye bolt with
gauze filter and
verify repair Go to Step 8
8 Is the ECM programmed with the latest software
release? If
not, download the latest software to the ECM using
the "SPS (Service Programming System)".
Was the problem solved? - Verify repair Go to Step 9
9 Substitute a known good ECM and recheck.
Was the problem solved?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobiliser system
(if equipped) must be linked to the ECM. Refer to
section 11 "Immobilizer System-ECM replacement" for
the ECM/Immobilizer linking procedure. - Go to Step 10Go to Step 11 Step Action Value(s) Yes No

6E–364 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
17 Remove the eye bolt with gauze filter from the
injection pump and check for the following conditions.
Objects blocking at the gauze filter. Check for a
condition that causes contaminated fuel, such as
the customer is using an aftermarket fuel filter or
ex tended maintenance interval.
Check for a condition that causes fuel wax ing or
icing, such as the customer is using an incorrect
fuel type in winter season or water mix ed with the
fuel.
If a problem is found, repair as necessary.
Was the problem found?
—Replace the
eye bolt with
gauze filter and
verify repair Go to Step 18
18 Check the engine compression pressure for each
cylinders.
If a problem is found, repair as necessary.
Was the problem found?
More than 2.1
Mpa (21.0 kg/
cm
2) Verify repair Go to Step 19
19 If the injection pump was replaced, are the timing
gears or injection pump correctly installed?
—Go to Step 20Repair as
necessary Step Action Value(s) Yes No

6E–368 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
15 Remove the eye bolt with gauze filter from the
injection pump and check for the following conditions.
Objects blocking at the gauze filter. Check for a
condition that causes contaminated fuel, such as
the customer is using an aftermarket fuel filter or
ex tended maintenance interval.
Check for a condition that causes fuel wax ing or
icing, such as the customer is using an incorrect
fuel type in winter season or water mix ed with the
fuel.
If a problem is found, repair as necessary.
Was the problem found?
—Replace the
eye bolt with
gauze filter and
verify repair Go to Step 16
16 Remove the injection nozzles from the engine and
check for the following conditions.
Improper splay condition.
Operating pressure is incorrect.
If a problem is found, repair as necessary.
Was the problem found?
—Replace the
injection nozzle
and verify repair Go to Step 17
17 Check the engine compression pressure for each
cylinders.
If a problem is found, repair as necessary.
Was the problem found?
More than 2.1
Mpa Verify repair Go to Step 18 Step Action Value(s) Yes No
1st Stage 2nd Sta ge
4JA1-TCApproximatly
19.0 MpaApprox ima tly
33.5 Mpa
4JH1-TCApproximatly
19.5 MpaApprox ima tly
33.8 Mpa