2007 ISUZU KB P190 service

ENGINE MECHANICAL 6A – 75










































2. Measure the piston diameter.

Piston Measuring Point mm (in)
4JA1T(L) 4JA1TC 78 (3.07)
4JH1TC 70
(2.76)


Piston Grade (Service Part) mm (in)
AX 92.949 - 92.964
(3.6549 - 3.6600)
4JA1T(L) 4JA1TC CX 92.965 - 92.980
(3.6600 - 3.6606)
AX 95.359 - 95.374
(3.7542 - 3.7548)
4JH1TC
CX 95.375 - 95.390
(3.7548 - 3.7555)


Cylinder Liner and Piston Clearance mm (in)
4JA1T(L) 4JA1TC 0.041-0.071 (0.0016-0.0027)
4JH1TC 0.047-0.065
(0.0019-0.0026)

NOTE:
Cylinder liner kit clearances are preset. However, the
cylinder liner installation procedure may result in
slight decreases in cylinder liner clearances. Always
measure the cylinder liner clearance after installation
to be sure that it is correct.



TAPPET AND PUSH ROD
Visually inspect the tappet contact surfaces for pitting,
cracking, and other abnormal conditions. The tappet must be
replaced if any of these conditions are present.
Refer to the illustration at the left.
1. Normal contact
2. Cracking
3. Pitting
4. Irregular contact Uneven contact
5. Irregular contact One-sided contact

NOTE:
The tappet surfaces are spherical. Do not attempt to
grind them with an oil stone or similar tool in an effort
to repair the tappet. If the tappet is damaged, it must
be replaced.


015LX021
014RY00028

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ISUZU KB P190 2007

ENGINE MECHANICAL 6A – 85
CRANKSHAFT PILOT BEARING
Check the crankshaft pilot bearing for excessive wear and
damage and replace it if necessary.















Crankshaft Pilot Bearing Replacement
Crankshaft Pilot Bearing Removal
Use the pilot bearing remover to remove the crankshaft pilot
bearing.
Pilot Bearing Remover: 5-8840-2000-0
Sliding Hammer: 5-8840-0019-0
















Crankshaft Pilot Bearing Installation
1. Place the crankshaft pilot bearing right angle across the crankshaft bearing installation hole.
2. Tap around the edges of the crankshaft pilot bearing outer races with a brass hammer to drive the bearing into the
crankshaft bearing installation hole.
Pilot Bearing Installer: 5-8522-0024-0

NOTE:
Strike only the crankshaft pilot bearing outer race with
the hammer. Do not strike the bearing inner race.
Bearing damage and reduced bearing service life will
result.







































FLYWHEEL AND RING GEAR
Flywheel
1. Inspect the flywheel friction surface for excessive wear and
heat cracks.
2. Measure the flywheel friction surface depth. If the measured value is within the specified limit, the
flywheel may be reground.
If the measured value exceeds the specified limit, the
flywheel must be replaced.

Flywheel Friction Surface Depth (1) mm (in)
Standard Limit
4JA1T (L),
4JA1TC 20 (0.7874) 21 (0.8267)
4JH1TC 18 (0.7087) 19 (0.7480)

Ring Gear
Inspect the ring gear.
If the ring gear teeth are broken or excessively worn, the ring
gear must be replaced.
015RY00010
015RY00019 015RY00018

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ISUZU KB P190 2007

6B – 8 ENGINE COOLING
Draining and Refilling Cooling System
Before draining the cooling system, inspect the system and
perform any necessary service to ensure that it is clean, does
not leak and is in proper working order. The engine coolant
(EC) level should be between the “MIN" and “MAX" lines o
f
reserve tank when the engine is cold. If low, check for leakage
and add EC up to the “MAX" line.
There should not be any excessive deposit of rust or scales
around the radiator cap or radiator filler hole, and the EC
should also be free from oil.
Replace the EC if excessively dirty.


P1010064
1. Completely drain the cooling system by opening the drain
plug at the bottom of the radiator.

2. Remove the radiator cap.
WARNING: To avoid the danger of being burned, do not
remove the cap while the engine and radiator are still hot.
Scalding fluid and steam can be blown out unde
r
pressure.
3. Disconnect all hoses from the EC reserve tank.
Scrub and clean the inside of the reserve tank with soap and water. Flush it well with clean water, then drain it.
Install the reserve tank and hoses.
4. Refill the cooling system with the EC using a solution that is at least 50 percent antifreeze.

Procedure for filling with coolant (in case of full change)
• Make sure that the engine is cool.
• Open radiator cap pour coolant up to filler neck.
• Pour coolant into reservoir tank up to “MAX" line.
• 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.
WARNING: When the coolant is heated to a high
temperature, be sure not to loosen or remove the radiato
r
cap. Otherwise you might get scalded by not 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.


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ISUZU KB P190 2007

FUEL SYSTEM 6C – 27

REASSEMBLY AND ADJUSTMENT PROCEDURE
1 First nozzle opening pressure adjustment Adjust the first nozzle opening pressure using the shim.

2
Full needle valve lift confirmation Confirm the full needle valve lift in accordance with the
closed method.

3 Pre-lift confirmation

Confirm pre-lift in accordance with the closed method.

CAUTION:
If not as specified, replace the nozzle assembly, lift
piece, pins and spacer using the nozzle service kit.
4
Second nozzle opening pressure
confirmation Confirm the second nozzle opening pressure in accordance
with the closed method.

5 Second nozzle opening pressure
adjustment Adjust the second nozzle opening pressure using the shim.

6
Final inspection Confirm the condition of the fuel spray with the nozzle and
nozzle holder assembled.







First nozzle opening pressure adjustment
Nozzle needle valve full-lift 0.25 mm (0.0098 in)
Nozzle needle valve pre-lift 0.04 mm(0.0016 in) at 20,000 kPa (2901 psi, 204 kg/cm2)
Nozzle pressure
4JA1T(L) 1st Stage 19.1 MPa (2759 psi, 194 kg/cm2)
2nd Stage 25.5-27.0 MPa (3768-3911 psi, 260-275 kg/cm2)

NOTE: Only 4JA1L can perform adjustment of a nozzle.

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FUEL SYSTEM 6C – 33

2. Read the needle valve “pre-lift” point from the dial gauge indication (once the needle valve has
descended when the second spring has stopped
operating).
Pre-lift measuring point:
Read the dial gauge at first nozzle opening pressure +approx
1 MPa (10 kg/cm
2).
Pre-lift mm
Pressure Mpa
(psi/ kg/cm
2) Lift mm (in)
4JA1T(L) 20.1 (2,858/205) 0.04 (0.0016)
Note:
This point can be found while the pressure is
decreasing.

3. Confirm that pre-lift is as specified.
4. If pre-lift is not as specified, replace the pins, lift piece, spacer and nozzle assembly as a set with the service
kit.
Service kit
105017-2990 (Bosch AS)
897302-3070 (ISUZU)

Second nozzle opening pressure confirmation
1. After pre-lift confirmation, operate the nozzle tester to increase in-line pressure to 34.3 - 44.1 MPa (350 - 450
kg/cm
2) so that the nozzle’s needle valve moves
through its full lift.


040MV005.tif
040MV031.tif
040MV030.tif 040H100007

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6C – 36 FUEL SYSTEM
4. Set the nozzle holder to the nozzle tester and check
first nozzle opening pressure, spray condition, seat oil
tightness and each part for oil leaks.
5. W hen replacing the nozzle, replace the nozzle, lift piece, pins and spacer as a set with the nozzle service
kit.
CAUTION:
Pre-lift will not be as specified if only the nozzle is
replaced.


040MV030.tif

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Engine Control System (4JH1) 6E-3
Rough, Unstable, or In co rr ect Idle And
Stallin g........................................................... .6E -260
Cut Out, Mi sses.............................................. .6E -262
Su rge s/Chuggle s............................................ .6E -263
La ck of Po wer, Sluggi shne ss, Spongine ss .... .6E -266
He sitation, Sag, Stu mble................................ .6E -268
Fuel Kno ck /Co mbu stion Noi se ....................... .6E -270
Poor F uel E cono my........................................ .6E -271
E xc ess ive S moke (B la ck S m oke) ................. .6E -272
E xc ess ive S moke (W hite S moke) ................. .6E -273
Repair In str u ctions ............................................ .6E -275
Engine Control Module (ECM) Replacement ..6E-275
Service Programming System (SPS)
Description .....................................................6E-276
Service Programming System (SPS)
(Remote Procedure) ......................................6E-277
Service Programming System (SPS)
(Pass-Thru Procedure) ..................................6E-278
Accelerator Pedal Position (APP) Sensor
Replacement ..................................................6E-279
Crankshaft Position Sensor (CKP) Sensor
Replacement ..................................................6E-279
EGR Solenoid Valve Replacement .................6E-280
Engine Coolant Temperature Coolant
(ECT) Sensor Replacement ...........................6E-280
Mass Air Flow (MAF) / Intake Air Temperature
Sensor Replacement......................................6E-280
Turbocharger Solenoid Valve Replacement
[High Altitude Spec] ........................................6E-281
Vacuum Pressure Sensor Replacement
[High Altitude Spec] ........................................6E-281
Vehicle Speed Sensor (VSS) Replacement ....6E-282
Description And Operation .................................6E-283 Engine Control Module (ECM) .......................6E-283
Engine Control Component Description ..........6E-284
Fuel Injection System Description ...................6E-288
Low Pressure Fuel Circuit Description ............6E-290
High Pressure Fuel Circuit Description ...........6E-291
Timing Control Device Description ..................6E-294
Exhaust Gas Recirculation (EGR) System
Description .....................................................6E-297
Turbocharger Description................................6E-298
Special Tools And Equipment ............................6E-299 Special Tools and Equipment .........................6E-299


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Engine Control System (4JH1) 6E-33
Diagnostic System Check - Engine
Controls
Description
The Diagnostic System Check-Engine Controls is an
organized approach to identifying a condition that is
created by a malfunction in the electronic engine control
system. The Diagnostic System Check must be the
starting point for any driveability concern. The
Diagnostic System Check directs the service technician
to the next logical step in order to diagnose the concern.
Understanding and correctly using the diagnostic table
reduces diagnostic time, and prevents the replacement
of good parts.
Test Description
The numbers below refer to the step numbers on the
diagnostic table.
2. Lack of communication may be because of a partial
or a total malfunction of the Keyword 2000 serial data
circuit. The specified procedure determines the
particular condition.



11. If there are other modules with DTCs set, refer to
the DTC list. The DTC list directs you to the appropriate
diagnostic procedure. If the control module stores
multiple DTCs, diagnose the DTCs in the following
order.
• Component level DTCs, such as sensor DTCs,
solenoid DTCs, actuator DTCs, and relay DTCs.
Diagnose the multiple DTCs within this category in
numerical order. Begin with the lowest numbered
DTC, unless the diagnostic table directs you
otherwise.
Important:

• DO NOT perform this diagnostic if there is not a
driveability concern, unless another procedure
directs you to this diagnostic.
• Before you proceed with diagnosis, search fo
r
applicable service bulletins.
• Unless a diagnostic procedure instructs you, DO
NOT clear the DTCs.
• If there is a condition with the starting system, refe
r
to the starting system section in the engine
mechanical.
• Ensure the battery has a full charge.
• Ensure the battery cables (+) (-) are clean and
tight.
• Ensure the ECM grounds are clean, tight, and in
the correct location.
• Ensure the ECM harness connectors are clean and
correctly connected.
• Ensure the ECM terminals are clean and correctl
y
mating.
• Ensure the fuel injection pump control unit (PCU)
ground is clean, tight, and in the correct location.
• Ensure the PCU harness connectors are clean and
correctly connected.
• Ensure the PCU terminals are clean and correctl
y
mating.
• Ensure the vehicle maintenance has been done
enough.

Step Action Value(s) Yes No
1 Install the scan tool.
Does the scan tool turn ON? 

Go to Step 2 Go to scan tool
Does Not Power Up

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