
HEATER AND AIR CONDITIONING 1-53
Checking and Adjusting for Compressor
Replacement
180 cm3 (5.07 lmp fl oz) of oil is charged in compressor
(service parts). So it is necessary to drain the proper amount
of oil from the new compressor.
1) Perform oil return operation.
2) Discharge refrigerant and remove the compressor.
3) Drain the compressor oil and measure the extracted oil.
4) Check the compressor oil for contamination.
5) Adjust oil level as required.
Amount of oil drained
From used compressor Draining amount of oil
From new compressor
less than
90 cm
3 (2.53 lmp fl oz) Some as drained
amount
more than
90 cm
3 (2.53 lmp fl oz) 90 cm
3 (2.53 lmp fl oz)
6) Evacuate, charge and perform oil return operation.
7) Check system operation.
CONTAMINATION OF COMPRESSOR OIL
Unlike engine oil, no cleaning agent is added to the
compressor oil. Even is the compressor runs for a long period
of time (approximately 1 season), the oil never becomes
contaminated as long as there is nothing wrong with the
compressor or its method of use.
Inspect the extracted oil for any of the following
conditions:
• The capacity of the oil has increased.
• The oil has changed color to red.
• Foreign substances, metal powder, etc., are present in the
oil.
If any of these conditions exists, compressor oil is
contaminated. Whenever contaminated compressor oil is
discovered, the receiver/drier must be replaced.
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ISUZU KB P190 2007

6 – 2 TROUBLESHOOTING
Basic Inspection Procedure
Follow the under inspection procedure, when the problem vehicle comes workshop. Step Inspection point Inspection result YES NO
1 Check the check engine lamp Is the check engine lamp turn ON ? Go to
section
6E “On Board Diagnostic
(OBD) System Check" Go to Step 2
2 The battery fluid level and the
gravity Was the problem found? Re-charge the
battery or
replace the battery Go to Step 3
3 The engine coolant capacity Was the problem found? Replenish the
engine coolant Go to Step 4
4 The engine oil level Was the problem found? Replenish the
engine oil Go to Step 5
5 The air cleaner element Was the problem found? Clean or
replace Go to Step 6
6 The piping fixing condition (oil,
vacuum and fuel piping) Was the problem found? Return normal
condition Go to Step 7
7 The drive belt tension and break Was the problem found? Re-adjust the
tension or replace Go to Step 8
8 Go to section 6E “On Board
Diagnostic (OBD) System
Check” Was the problem found?
Verify repair Go to Step 9
9 Go to mechanical
troubleshooting chart Was the problem found?
Verify repair —
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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
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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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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. 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.
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)
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.
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ENGINE COOLING 6B – 3
MAIN DATA AND SPECIFICATIONS
Description Item M/T A/T
Cooling system
W ater pump type
Pump to crankshaft speed ratio (To 1)
Delivery volume lit (US/UK gal)/min
Pump speed at 3000 rpm
W ater temperature at 30 °C (86 °F)
Pump bearing type
Thermostat type
Valve initial opening temperature °C ( °F)
(Oil cooler thermo valve)
(EGR cooler thermo valve)
Valve full opening temperature °C ( °F)
(Oil cooler thermo valve)
(EGR cooler thermo valve)
Valve lift at fully open position mm (in)
(Oil cooler thermo valve)
(EGR cooler thermo valve) Engine coolant forced circulation
Centrifugal impeller type 1.2
100 (26.3/22.2)
Double row shaft
W ax pellet with jiggle valve 82 (180)
76.5 (170) 40 (104)
95 (203)
90 (194)
55 (131)
9.5 (0.37)
4.5 (0.18)
3.5 (0.14)
Radiator Tube type corrugated
Heat radiation capacity 93.0 kW (79,980 kcal/h)
Heat radiation area 11.63 m2 (1.081ft2)
Radiator front area 0.28m2 (0.026 ft2)
Radiator dry weight 52 N (5.3 kg/11.7 lb) 53 N (5.4 kg/11.9 lb)
Radiator cap valve opening pressure 93.3 ~ 122.7 kPa (13.5 ~ 17.8 psi)
Engine coolant capacity 2.4 lit (5.1 U.S pint) 2.3 lit (4.9 U.S pint)
Engine coolant total capacity 10.1 lit (21.3 U.S pint) 10.0 lit (21.1 U.S pint)
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6B – 6 ENGINE COOLING
110RS001
RADIATOR
The radiator is a tube type with corrugated fins. In order to
raise the boiling point of the coolant, the radiator is fitted with a
cap in which the valve is operated at 93.3
∼ 122.7 kPa (13.5 ∼
17.8 psi) pressure. (No oil cooler provided for M/T)
F06RW 005
Antifreeze Solution
NOTE: Antifreeze solution + W ater = Total cooling system
capacity.
Total Cooling System Capacity Lit (US / UK gal)
9.4 (2.5/21) 4JA1L/TC
M/T 10.1 (2.7/2.2) 4JH1TC
A/T 10.0 (2.6/2.2) 4JH1TC
See section 0B MAINTENACE AND LUBRICATION .
PTW 46BSH000201
NOTE:
To maintain the corrosion resistance of the aluminum
radiator, water and antifreeze must be combined in a 1:1
solution (50% antifreeze and 50% water)
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ISUZU KB P190 2007

ENGINE COOLING (4JK1/4JJ1) 6B-5
Radiator
The radiator is a tube type with corrugated fins. In order
to raise the boiling point of the coolant, the radiator is
fitted with a cap in which the valve is operated at 93.3 -
122.7 kPa (0.95 - 1.25 kg / cm
2 / 13.5 - 17.8 psi)
pressure. (No oil cooler provided for M/T)
RTW 56BSH000301
Antifreeze Solution
NOTE:
Antifreeze solution + W ater = Total cooling system
capacity.
Total Cooling System Capacity Lit
(US / UK gal) (US pint)
M/T 8.7 (2.3/1.9) (18.4)
A/T 8.6 (2.3/1.9) (18.2)
See section 0B MAINTENANCE AND LUBRICATION .
F06RW 005
NOTE:
To maintain the corrosion resistance of the aluminum
radiator, water and antifreeze must be combined in a
1:1 solution (50% antifreeze and 50% water).
RTW 76BSH000201
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