Page 1737 of 3573

6A – 4 ENGINE MECHANICAL
Engine Cooling
Starting System
Cooling system Coolant forced circulation
Radiator (2 tube in row) Tube type corrugated
Heat radiation capacity J/h (kcal/h) 318 x 10
6(76000)
Heat radiation area m
2(ft2) 15.63 (1.454)
Front area m
2(ft2) 0.309 (2.029)
Dry weight N (kg/lb) 83 (8.5/18.7)
Radiator cap
Valve opening pressure kPa (kg/cm
2/ psi) 93.3 – 122.7 (0.95 – 1.25/13.5 – 17.8)
Coolant capacity lit (Imp.qt./US qt.) M/T 2.5 (2.2/2.6) A/T 2.4 (2.1/2.5)
Coolant pump Centrifugal impeller type
Pulley ratio (to 1) 1.2
Coolant total capacity lit (Imp.qt./US qt.) 9.3 (8.2/9.8)
Model HITACHI S14-0
Rating
Voltage V 12
Output kW 2.8
Time sec 30
Number of teeth of pinion 9
Rotating direction (as viewed from pinion) Clockwise
Weight (approx.) N(kg/lb) 49 (5.0/11)
No-load characteristics
Voltage/current V/A 11/160 or less
Speed rpm 4000 or more
Load characteristics
Voltage/current V/A 8.76/300
Torque N·m(kg·m/lb·ft) 7.4 (0.75/5.4) or more
Speed rpm 1700 or more
Locking characteristics
Voltage/current V/A 2.5/1100 or less
Torque N·m(kg·m/lb·ft) 18.6 (1.9/14) or more
Page 1738 of 3573
ENGINE MECHANICAL 6A – 5
Charging System
Model (HITACHI) LR190-750B LR1100 – 731
Rated voltage V 12
Rated output A 90 100
Rotation direction
Clockwise
(As viewed from pulled)
Pulley effective diameter mm (in) 69 (2.72)
Weight N (kg/lb) 52 (5.3/11.7)
Page 1739 of 3573

6A – 6 ENGINE MECHANICAL
SERVICE STANDARD
Enginemm (in)
Parts Items Service standard Service limit Remarks
Cylinder Head
Valve Spring
Valve and
Valve guide
Camshaft0.075 (0.0030) or less
95.0 (3.740)
45.7 (1.8)
—
241 (54.2)
6.959 – 6.977
(0.27 –0.272)
6.692 –6.970
(0.271 –0.272)
0.023 –0.056
(0.0009 – 0.0022)
0.03 – 0.063
(0.0011 – 0.0024)
8.0 (0.312)
1.1 (0.0433)
1.2 (0.0472)
1.2 (0.0472)
45°
2.1 (0.0827)
2.1 (0.0827)
0.08 (0.00314)
46.67 (1.8374)
46.77 (1.8413)
29.939 – 29.960
(1.167 – 1.168)
0.02 (0.0008) or less
0.40 – 0.082
(0.0016 – 0.0032)0.50 (0.0197)
—
44.8 (1.765)
1.6 (0.063)
210 (47.22)
6.92 (0.270)
6.90 (0.269)
0.19 (0.0074)
0.20 (0.0079)
—
1.6 (0.0630)
1.1 (0.0433)
1.1 (0.0433)
—
2.6 (0.1024)
2.6 (0.1024)
2.0 (0.00797)
46.57 (1.8335)
46.67 (1.8374)
29.84 (1.1748)
0.10 (0.0039)
0.12 (0.0047)Cannot be
reground Cylinder head lower surface for flatness
Cylinder head height
Free height
Squareness
Spring tension (when assembled) N(lb)
Diameter of Valve stem IN
EX
Valve and valve guide clearance IN
EX
Valve guide upper end height
(Measured from the Cylinder head upper
face)
Valve guide margin
Valve thickness IN
EX
Valve seat contact surface angle
Valve seat contact width IN
EX
End play
Cam lobe height IN
EX
Journal diameter
Runout
Camshaft oil clearance
Page 1740 of 3573

ENGINE MECHANICAL 6A – 7
Parts Items Service standard Service limit Remarks
Tappet
Crankshaft
Piston,
Piston pin,
Piston ring
and
Connecting
rod32.977 – 32.990
(1.2983 – 1.2988)
0.01 – 0.039
(0.0004 – 0.0015)
0.04 – 0.20
(0.0016 – 0.0079)
0.037 – 0.068
(0.0015 – 0.0027)
0.05 (0.0020) or less
69.917 – 69.932
(2.7526 – 2.7532)
52.915 – 52.930
(2.0933 – 2.0839)
95.32 – 95.349
(3.7527 – 3.7539)
0.11 – 0.92
(0.0043 – 0.0362)
0.25 – 0.40
(0.0098 –0.0157)
0.20 –0.35
(0.0079 – 0.0138)
0.10 – 0.30
(0.0039 – 0.0118)
0.05 – 0.09
(0.0020 – 0.0035)
0.03 – 0.07
(0.00118 – 0.00276)
30.995 – 31.000
(1.203 – 1.205)
0.008 – 0.020
(0.0003 –0.00079)
0.005 – 0.018
(0.0002 – 0.0007)
0.08 (0.031) or less
0.05 (0.0020) or less
0.230 (0.0091)
0.022 – 0.042
(0.0009 – 0.0017)32.950 (1.2972)
0.10 (0.0039)
0.30 (0.00118)
0.11 (0.0043)
0.08 (0.0031)
69.91 (2.7524)
52.90 (2.0827)
—
—
1.5 (0.0590)
1.5 (0.0590)
1.5 (0.0590)
0.15 (0.0059)
0.15 (0.0059)
30.97 (1.2078)
0.05 (0.0020)
0.04 (0.0016)
0.20 (0.00787)
0.15 (0.0059)
0.35 (0.0138)
0.0060
(0.0024)Uneven
wear limit
0.05 (0.002)
Uneven
wear limit
0.08 (0.0031)
Per 100
(3.94)
Per 100
(3.94) Outside diameter
Oil clearance
Thrust clearance
Main bearing oil clearance
Crankshaft runout
Main journal diameter
Crank pin diameter
Piston diameter
Piston clearance
Piston ring gap 1st
2nd
Oil
Piston ring clearance 1st/2nd
Oil
Piston pin diameter
Piston pin clearance
(Between connecting rod and piston pin)
Piston pin clearance
(Between piston and piston pin)
Connecting rod alignment Bend
Twist
Connecting rod thrust clearance
Oil clearance
(Between crank pin and Connecting rod)
mm (in)
Page 1741 of 3573
6A – 8 ENGINE MECHANICAL
Parts Items Service standard Service limit Remarks
Cylinder
Block—
95.421 – 95.450
(3.7567 – 3.7579)0.20 (0.0079) Warpage
(Upper surface of the cylinder block)
Cylinder bore diameter
Parts Items Service standard Service limit Remarks
Thermostat
Radiator cap83 – 87°C
(181 – 189°F)
More than 9.5 (0.374)
at 100°C (212°F)
88.2 – 117.6 kPa
(12.8 –17.0 psi) Valve opening temperature
Valve full open temperature and lift
Valve opening pressure
Engine Coolingmm (in) mm (in)
Page 1742 of 3573

ENGINE MECHANICAL 6A – 9
SERVICING
Servicing refers to general maintenance procedures to
be performed by qualified service personnel.
MODEL IDENTIFICATION
Engine Serial Number
The engine number is stamped on the rear left hand
side of the cylinder body.
AIR CLEANER
Oil Wetted (Viscous) Type Paper Element.
The air cleaner has an oil wetted paper element. No
servicing is required until the replacement interval is
reached.
Never attempt to clean the element, no matter how dirty
it may appear. The element is designed to provide
normal filtering efficiency until it becomes due for
replacement.
Refer to the Item “Service and Maintenance” in the
Owner’s and Driver’s Manual for general service
information.
LUBRICATING SYSTEM
Main Oil Filter (Cartridge Type Paper Element)
Replacement Procedure
1. Loosen the drain plug to drain the engine oil.
2. Wait a few minutes and then retighten the drain
plug.
3. Loosen the used oil filter (2) by turning it counter-
clockwise with the filter wrench.
4. Clean the oil filer gasket fitting face.
This will allow the new oil filter to seat properly.
5. Apply a light coat of engine oil to the O-ring.
6. Turn the new oil filter until the filter O-ring is fitted
against the sealing face.
7. Use the filter wrench to turn the filter additional one
and 1/4 turns.
Filter Wrench: 5-5540-0203-0
012RW115
012RW062
For Europe1
2
050R200001
Page 1743 of 3573

6A – 10 ENGINE MECHANICAL
8. Check the engine oil level and replenish to the
specified level if required.
9. Start the engine and check for oil leakage from the
main oil filter.
FUEL SYSTEM
Fuel filter
Replacement Procedure
1. Loosen the used fuel filter by turning it
counterclockwise with the filter wrench.
Filter Wrench : 5-8840-0203-0
2. Clean the filter cover 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 the fuel filter until the sealing face comes in
contact with the O-ring.
5. Turn the fuel filter with a filter wrench 2/3 of a turn
until sealed.
Filter Wrench: 5-8840-0203-0Legend
(1) Priming pump
6. Operate the priming pump until the air is discharged
completely from fuel system.
NOTE: The use of an Isuzu genuine fuel filter is
strongly recommended.
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.
NOTE: Do not overfill the reserve tank.
012RW112
012RW078
1
012RW111
012RW080
Page 1744 of 3573

ENGINE MECHANICAL 6A – 11
Remove the radiator filler cap only when absolutely
necessary.
Always check the coolant level when the engine is cold.
Always refer to the chart at the left to determine the
correct cooling water to antifreeze solution mixing ratio.
Cooling System Inspection
Install a radiator filler cap tester to the radiator. Apply
testing pressure to the cooling system to check for
leakage.
The testing pressure must not exceed the specified
pressure.
Testing Pressure: 196 kPa (2 kg/cm
2/28.45 psi)
Radiator Cap Inspection
The radiator filler cap is designed to maintain coolant
pressure in the cooling system at 103 kPa (1.05
kg/cm
2/15 psi).
Check the radiator filler cap with a radiator filler cap
tester.The radiator filler cap must be replaced if it fails to hold
the specified pressure during the test procedure.
Radiator Filler Cap Pressure Valve: 88.2 – 117.6 kPa
(0.899 – 1.199 kg/cm
2/12.8 – 17.1 psi)
Negative Valve (Reference): 1.0 – 3.9 kPa
(0.01 – 0.04 kg/cm
2/0.14 – 0.57 psi)
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:
83 – 87°C (181 – 189°F)
4. Check the thermostat full opening temperature.
Thermostat Full Opening Temperature:
100°C (212°F)
Valve Lift at Fully Open Position: 9.5 mm (0.374
in)0
-10
-20
-30
-40
-50
-60
10 20 30
Mixing ratio (%)
Freezing point ( °C)
40 50 60
111RW002
110RS005
110RS006
031RS003