
0B-2 MAINTENANCE AND LUBRICATION
MAINTENANCE SCHEDULE (For GENERAL EXPORT)
Items followed by an asterisk (*) require more frequent maintenance if the vehicle is driven under severe conditions.
Replace the fuel filter (**Mark) when the fuel filter indicator light is lit.
Refer to "SEVERE CONDITIONS MAINTENANCE SCHEDULE."
I : Inspect and correct or replace as necessary A : Adjust
R : Replace or change T : Tighten to specified torque L : Lubricate
SERVICE INTERVAL: × 1,000 km 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100(Use odometer reading × 1,000 miles 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60or months whichever
comes first)
or months 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120
ENGINE
Idling speed and acceleration
(GASOLINE) I I - I - I - I - I - I - I - I - I - I (DIESEL) I I I I I I I I I I I I I I I I I I I I * Air cleaner element
(GASOLINE) - I - I - I - R - I - I - I - R - I - I (DIESEL) I I I I I I I R I I I I I I I R I I I I * Engine oil (HFV6) - - R - - R - - R - - R - - R - - R - - (C24SE) Replace every 12,000km (4JH1-TC, 4JJ1 (Standard Output),
4JJ1 (High Output)) - R - R - R - R - R - R - R - R - R - R
(4JA1-T) R R R R R R R R R R R R R R R R R R R R * Engine oil filter (HFV6) - - R - - R - - R - - R - - R - - R - - (C24SE) Replace every 12,000km (4JH1-TC, 4JA1-T) - R - R - R - R - R - R - R - R - R - R (4JJ1 (Standard Output),
4JJ1 (High Output)) - - - R - - - R - - - R - - - R - - - R
Oil leakage and contamination (GASOLINE) - I - I - I - I - I - I - I - I - I - I (DIESEL) I I I I I I I I I I I I I I I I I I I I Fuel leakage
I I - I - I - I - I - I - I - I - I - I Fuel tank - - - I - - - I - - - I - - - I - - - I O2 Sensor (C24SE) Replace every 160,000km (HFV6)
MIL diagnostic Indicates O2 Sensor Valve clearances (6VE1) Check and adjust if noisy (4JH1-TC, 4JA1-T) A - - A - - - A - - - A - - - A - - - A (4JJ1 (Standard Output),
4JJ1 (High Output)) - - - - - - - A - - - - - - - A - - - -
Spark plugs (C24SE) (for leaded fuel
use) - R - R - R - R - R - R - R - R - R - R
Spark plugs (C24SE) (for unleaded
fuel use) - - - - - R - - - - - R - - - - - R - -
Spark plugs
(HFV6) Replace every 120,000km Spark plug wire - - - - - - - - - - - - - - - - - - - I Fuel filter (GASOLINE) - - - R - - - R - - - R - - - R - - - R (4JH1-TC, 4JA1-T) - - R - - R - - R - - R - - R - - R - - ** (4JJ1 (Standard Output),
4JJ1 (High Output)) Replace the fuel filter when the fuel filter indicator light is lit.
Fuel pump in fuel tank
(4JJ1 (Standard Output),
4JJ1 (High Output)) - - - - - - - I - - - - - - - I - - - -
Engine / Accessory drive belt
(C24SE) - - - - - - - - - I - - - - - - - - - I
(HFV6) Replace every 100,000km Fan belt tension and damage
(DIESEL) I I I I I I I I I I I I I I I I I I I I
* Exhaust system
I I - I - I - I - I - I - I - I - I - I Engine coolant concentration (HFV6) - I - I - I - I - I - I - I - I - I - R (C24SE) - I - I - I - I - R - I - I - I - I - R (DESEL) - I - I - I - I - I - I - I - I - I - I Engine coolant
(4JJ1 (Standard Output),
4JJ1 (High Output)) Change every 2 years
Cooling system for water leakage - I - I - I - I - I - I - I - I - I - I All hoses and pipes in engine
compartment for clogs or damage - I - I - I - I - I - I - I - I - I - I
Timing belt
(C24SE) - - - - - - - - - - - - - - - I - - - - Replace every 120,000km Timing belt (6VE1) Replace every 160,000km
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6A – 2 ENGINE MECHANICAL
Disassembly ............................................................................................................... 6A- 47
Internal Parts .......................................................................................................... 6A- 47
Major Components ............................................................................................. 6A- 47
Minor Components ............................................................................................. 6A- 56 Rocker Arm Shaft and Rocker Arm ............................................................... 6A- 56
Cylinder Head .................................................................................................. 6A- 57
Piston and Connecting Rod ........................................................................... 6A- 59
Inspection and Repair ............................................................................................... 6A- 61 Cylinder Head ......................................................................................................... 6A- 61
Rocker Arm Shaft and Rocker Arm....................................................................... 6A- 68
Cylinder Body ......................................................................................................... 6A- 69
Camshaft ................................................................................................................. 6A- 7 7
Crankshaft and Bearing ......................................................................................... 6A- 79
Crankshaft Bearing Selection ............................................................................... 6A- 83
Crankshaft Pilot Bearing ....................................................................................... 6A- 85
Flywheel and Ring Gear......................................................................................... 6A- 85
Piston ...................................................................................................................... 6A - 86
Cylinder Head Gasket Selection ........................................................................... 6A- 88
Connecting Rod...................................................................................................... 6A- 90
Idler Gear Shaft and Idler Gear ............................................................................. 6A- 91
Timing Gear Case Cover........................................................................................ 6A- 91
Reassembly ................................................................................................................ 6A- 93
Internal Parts .......................................................................................................... 6A- 93
Minor Component ............................................................................................... 6A- 93 Rocker Arm Shaft and Rocker Arm ............................................................... 6A- 93
Cylinder Head .................................................................................................. 6A- 94
Piston and Connecting Rod ........................................................................... 6A- 96
Positive Crankcase Ventilation (PCV) Valve ................................................. 6A- 99
Major Component ............................................................................................... 6A- 101
Installation .................................................................................................................. 6A- 118
External Parts ......................................................................................................... 6A- 118
Lubrication System ....................................................................................................... 6A- 1 26
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6A – 4 ENGINE MECHANICAL
MAIN DATA AND SPECIFICATIONS
Engine model
Item 4JA1T (L)
4JA1TC
Engine type
Combustion chamber type
Cylinder liner type
Timing gear train system Four-cycle, overhead valve, water cooled
Direct injection
Dry type, chrome plated Gear drive
No. of cylinders-bore × stroke mm (in) 4 – 93 × 92 (3.66 × 3.62)
No. of piston rings Compression ring: 2 / Oil ring: 1
Total piston displacement cm3 (in3)
Compression ratio (to 1) 2,499 (152.4)
18.5
Compression pressure MPa (kg/cm2/psi) 3.0 (31.0/441) – 200 rpm
Engine weight (dry) kg (lb)Approximately 239 (527)
Fuel injection order 1 – 3 – 4 - 2
Fuel injection timing BTDC deg8 -
Specified fuel type
Idling speed rpm
Valve clearances (At cold): Intake mm (in)
Exhaust mm (in)
Intake valves Open at (BTDC) deg
Close at (ABDC) deg
Exhaust valves Open at (BBDC) deg
Close at (ATDC) deg
Fuel system JIS No. 2, DIN/EN590, GB252-1944 Diesel fuel
730 ± 25 (A/C Off)
780 ± 25 (A/C ON)
0.4 (0.016)
0.4 (0.016) 24.5
55.5
54.0
26.0
Injection pump type BOSCH distributor VE type BOSCH distributor VP44 type
Governor type Mechanical (Half all speed
type) Electronically controled
Injection nozzle type
Injection nozzle opening pressure Hole with 5 orifices
MPa (kg/cm2/psi) 1st 19.1 (195 / 2,773) 1st 19.0 (194 / 2,755)
2nd (Reference)
25.5 ∼27.0
(260 ∼275 / 3,702 ∼3,920) 2nd (Reference)
34.0 ∼35.5
(347 ∼362 / 4,936 ∼5,154)
Main fuel filter type
Lubricating system
Lubricating method Cartridge paper element and water separator
Pressure circulation
Specified engine oil (API grade) ISUZU genuine 10W – 30 (API CD of ACEA B2/B3)
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6A – 6 ENGINE MECHANICAL
MAIN DATA AND SPECIFICATIONS
Engine model
Item 4JH1TC
Engine type
Four-cycle, overhead valve, water cooled
Combustion chamber type Direct injection
Cylinder liner type
Timing gear train system Dry type, chrome plated
Gear drive
No. of cylinders-bore × stroke mm (in) 4 – 95.4 × 104.9 (3.76 × 4.13)
No. of piston rings Compression ring: 2 / Oil ring: 1
Total piston displacement liter
Compression ratio (to 1) 2,999
18.3
Compression pressure MPa (kg/cm2/psi) 3.0 (31.0/441) – 200 rpm
Engine weight (dry) kg (lb)MT: Approximately 249 (549)
AT: Approximately 236 (520)
Fuel injection order 1 – 3 – 4 - 2
Specified fuel type JIS No.2, DIN/EN590, GB252-1944 Diesel fuel
Idling speed rpm
700 ± 25 (A/C OFF)
800 ± 25 (A/C ON)
Valve clearances (At cold): Intake mm (in)
Exhaust mm (in)
Intake valves Open at (BTDC) deg
Close at (ABDC) deg
Exhaust valves Open at (BBDC) deg
Close at (ATDC) deg
Fuel system
Injection pump type 0.4 (0.016)
0.4 (0.016) 24.5
55.5
54.0
26.0
BOSCH distributor VP44 type
Injection nozzle type
Injection nozzle opening pressure
MPa (kg/cm
2/psi) Hole with 5 orifices
1st 19.5 (199/2,828)
2nd (Reference) 34.3 ∼35.8 (350 ∼365/4,980 ∼5,197)
Main fuel filter type
Lubricating system
Lubricating method Cartridge paper element and water separator
Pressure circulation
Specified engine oil (API grade) ISUZU genuine 10W – 30 (API CD of ACEA B2/B3)
Oil pump type
Oil filter type Gear
Cartridge paper element
Oil capacity lit (US/UK gal)
6.2 (1.64/1.36) (For 4
× 2)
7.0 (1.85/1.54) (For 4 × 4)
Oil cooler type W ater cooled
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE MECHANICAL 6A – 11
Timing Gear Case, Pulley Housing, Timing Gear, and Camshaft
N·m (kg·m/lb·ft)
RTW 46AXF000601
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE MECHANICAL 6A – 31
VALVE CLEARANCE ADJUSTMENT
1. Bring the piston in either the No. 1 cylinder or the No. 4 cylinder to TDC on the compression stroke by turning
the crankshaft until the crankshaft damper pulley TDC
line is aligned with the timing pointer.
014RY00014
2. Check the rocker arm shaft bracket nuts for
looseness.
Tighten any loose rocker arm shaft bracket nuts
before adjusting the valve clearance.
Rocker Arm Shaft Bracket Nut Torque N·m (kg·m /lb·ft)
54 (5.5/40)
014RY00015
8. Check for play in the No. 1 intake and exhaust valve
push rods.
If the No. 1 cylinder intake and exhaust valve push
rods have play, the No. 1 piston is at TDC on the
compression stroke.
If the No. 1 cylinder intake and exhaust valve push
rods are depressed, the No. 4 piston is at TDC on the
compression stroke.
014RY00016
Adjust the No.1 or the No. 4 cylinder valve clearances
while their respective cylinders are at TDC on the
compression stroke.
Valve Clearance (At Cold) mm (in)
0.4 (0.016)
9. Loosen each valve clearance adjusting screw as
shown in the illustration.
10. Insert a feeler gauge of the appropriate thickness between the rocker arm and the valve stem end.
014RY00017
11. Turn the valve clearance adjusting screw until a slight
drag can be felt on the feeler gauge.
12. Tighten the lock nut securely.
13. Rotate the crankshaft 360 °.
14. Realign the crankshaft damper pulley TDC notched line with the timing pointer.
15. Adjust the clearances for the remaining valves as shown in the illustration.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE MECHANICAL 6A – 33
INJECTION TIMING ADJUSTMENT
(4JA1T(L) only)
1. Check that the notched line on the injection pump
flange is aligned with the front plate or the timing gear
case notched line.
2. Bring the piston in the No. 1 cylinder to TDC on the
compression stroke by turning the crankshaft until the
crankshaft pulley TDC line is aligned with the timing
mark.
Note:
Check for play in the No. 1 intake and exhaust valve
push rods.
If the No. 1 cylinder intake and exhaust valve push
rods have play, the No. 1 piston is at TDC on the
compression stroke.
RTW 46ASH000601
3. Disconnect the injection pipe from the injection pump
4. Remove one bolt from the distributor head.
5. Install the adapter set, togather with static timing gauge.
The probe of the gauge should be depressed inward
approximately 2 mm (0.079 in).
Static Timing Gauge: 5-8840-0145-0 (J-28827)
Adapter Set: Static Timing Gauge: 5-8840-2834-0
RTW 36ASH002101 6. Rotate the crankshaft to bring the piston in the No. 1
cylinder to a point 30 - 40 ° BTDC.
7. Set the timing gauge needle to zero.
8. Move the crankshaft pulley slightly in both directions to check that the gauge indication is stable.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6A – 34 ENGINE MECHANICAL
RTW 46ASH000701
9. Turn the crankshaft clockwise and read the gauge
indication when the crankshaft pulley timing mark (8 °)
is aligned with the pointer.
Injection Timing : BTDC 8 ° ± 2 °
Standard Reading mm (in)
0.5 (0.02)
If the injection timing is outside the specified range,
continue with the following steps.
10. Loosen the injection pump fixing nuts and bracket bolts.
11. Adjust the injection pump setting angle.
W hen large than standard value W hen smaller than standard
value
R A
A: Move the injection pump toward the engine.
R: Move the injection pump away from the engine.
12. Install the distributor head bolt.
Distributor head bolt torque N·m (kg·m /lb·ft)
29 (3.0/22)
ENGINE CONTROL (4JA1T(L) only)
Idling Speed Adjustment
1. Set the vehicle parking brake and chock the drive wheels.
2. Place the transmission in neutral.
3. Start the engine and allow it to idle until the coolant temperature reaches 70 - 80 °C (158 - 176 °F).
4. Disconnect the engine control cable from the control lever.
5. Set a tachometer to the engine.
6. Check the engine idling speed. If the engine idling speed is outside the specified
range, it must be adjusted.
Engine Idling Speed : 730 ± 25 rpm
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007