Page 809 of 6020

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)
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Page 811 of 6020

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
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Page 815 of 6020
6A – 10 ENGINE MECHANICAL
Crankshaft Bearing Cap, Connecting Rod Bearing Cap, Crankshaft Damper Pulley,
Flywheel, and Oil Pan
N·m (kg·m/lb·ft)
RTW 46AXF001401
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ISUZU KB P190 2007
Page 829 of 6020

6A – 24 ENGINE MECHANICAL
SERVICING
Servicing refers to general maintenance procedures to be performed by qualified service personnel.
RTW 36ASH000401
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 (Except wet type 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 W rench: 5-8840-0200-0
RTW 36ASH000101
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.
Filter W rench: 5-8840-0200-0
8. Check the engine oil level and replenish to the specified level if required.
130RY00003
6A-6
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Page 830 of 6020

ENGINE MECHANICAL 6A – 25
Replenished Engine Oil MAX lit (US/UK gal)
Condition
Model Engine Dry
W ith oil filter
replacement W ithout oil
filter
replacement
4 × 2
4 × 4
(4JA1L/TC)6.2 (1.64/1.36) 5.2 ∼ 4.2
(1.37 ∼ 1.11
/ 1.14 ∼ 0.92) 4.5
∼ 3.5
(1.19 ∼ 0.93
/ 0.99 ∼ 0.77)
4 × 2
(4JH1TC)
6.2 (1.64/1.36) 5.2
∼ 4.2
(1.37 ∼ 1.11
/ 1.14 ∼ 0.92) 4.5
∼ 3.5
(1.19 ∼ 0.93
/ 0.99 ∼ 0.77)
4 × 4
(4JH1TC) 7.0 (1.85/1.54) 6.2 ∼ 5.2
(1.64 ∼ 1.37
/ 1.36 ∼ 1.14) 5.3
∼ 4.3
(1.72 ∼ 1.14
/ 1.17 ∼ 0.95)
9. Start the engine and check for oil leakage from the
main oil filter.
RTW 66ASH003201
FUEL SYSTEM
Fuel Filter Replacement Procedure
1. Remove the fuel filter by turning it counterclockwise with a filter wrench.
Filter W rench: 5-8840-0253-0 (J-22700)
Note:
Be careful not to spill the fuel in the filter cartridge.
RTW 66ASH003301
2. Clean the fuel filter cartridge fitting faces. This will allow the new fuel filter to seat properly
3. Apply a light coat of engine oil to the O-ring.
4. Turn in the fuel filter until the sealing face comes in contact with the O-ring.
5. Turn in the fuel filter an additional 2/3 of a turn with a filter wrench.
Filter W rench : 5-8840-0253-0 (J-22700)
6. Operate the priming pump until the air discharged completely from fuel system.
7. Start the engine and check for fuel leakage.
Note:
The use of an ISUZU genuine fuel filter is strongly
recommended.
041RY00009
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ISUZU KB P190 2007
Page 832 of 6020

ENGINE MECHANICAL 6A – 27
111R300001
COOLING SYSTEM
Coolant Level
Check the coolant level and replenish the radiator reserve
tank as necessary.
If the coolant level falls below the “MIN” line, carefully
check the cooling system for leakage. Then add enough
coolant to bring the level up to the “MAX” line.
Engine coolant Filling up procedure
1. Make sure that the engine is cool.
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.
2. Open rediator cap pour coolant up to filler neck
3. Pour coolant into reservoir tank up to “MAX” line
4. 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.
5. 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.
6. Check to see the thermometer, continuously idling 5 minutes and stop the engine.
7. W hen 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.
8. Pour coolant into the reservoir tank up to “MAX” line.
Engine Coolant Total Capacity Lit (U.S / 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)
Mixing Ratio (Anti-Freeze Solution/W ater)
50 %
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ISUZU KB P190 2007
Page 834 of 6020

ENGINE MECHANICAL 6A – 29
Thermostat Operating Test
1. Completely submerge the thermostat in water.
2. Heat the water. Stir the water constantly to avoid direct heat being
applied to the thermostat.
3. Check the thermostat initial opening temperature.
Thermostat Initial Opening Temperature °C ( °F)
82 (180)
Oil Cooler Thermo Valve °C ( °F)
76.5 (170)
EGR Cooler Thermo Valve °C ( °F)
40 (104)
4. Check the thermostat full opening temperature.
Thermostat Full Opening Temperature °C ( °F)
95 (203)
Oil Cooler Thermo Valve °C ( °F)
90 (194)
EGR Cooler Thermo Valve °C ( °F)
55 (131)
Valve Lift at Fully Open position mm (in)
9.5 (0.37)
Oil Cooler Thermo Valve mm (in)
4.5 (0.18)
EGR Cooler Thermo Valve mm in)
3.5 (0.14)
Drive Belt Adjustment
Check drive belts for wear or damage, and replace with
new ones as necessary. Check belts for tension, and
adjust as necessary.
1 Crankshaft damper pulley
2 Generator pulley
3 Cooling fan pulley
4 Oil pump pulley or idler pulley
5 Compressor pulley or idler pulley
030LX014
033RY00002
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ISUZU KB P190 2007
Page 844 of 6020

ENGINE MECHANICAL 6A – 39
18. Radiator 1) Drain the engine coolant.
2) Remove the reservoir hose.
3) Remove the upper and lower hose.
4) Remove the fan guide.
5) Remove the radiator.
19. Fan
P1010034
20. Air cleaner
1) Remove the MAF sensor connector (4JA1TC/4JH1TC) from air cleaner duct.
2) Remove the air cleaner duct and the air cleaner box from engine room.
3) Remove the two air ducts from inter cooler (4JA1TC/4JH1TC).
21. Power Steering Pump Loosen the power steering pump adjust plate bolt, then
remove the power steering pump assembly. Place the
power steering pump assembly along with piping on the
body side.
22. Air conditioner compressor 1) Remove air compressor magnet connector.
2) Remove the air conditioner compressor. Place the air conditioner compressor along with piping on the body
side.
23. Engine Control Cable Remove the engine control cable from its bracket
(4JA1TC/4JH1TC) or the injection pump (4JA1T(L)).
24. Vacuum Piping Remove the vacuum pipe from the vacuum pump, the
EGR valve, injection pump FICD (4JA1T(L)).
25. Engine Harness 1) Remove following connectors from engine.
• TPS connector
• Oil pressure switch connector
• Thermo switch connector
• Injection pump connector
• Engine earth
• Thermometer unit connector
• TDC sensor
2) Remove the clips fixing engine harness.
P1010009
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