6A – 26 ENGINE MECHANICAL
041RY00011
Draining Procedure
The indicator light will come on when the water level in the
water separator exceeds the specified level.
Drain the water and foreign material from the water
separator (inside chassis frame) with the following
procedure.
1. Place the drain pan under the drain plug.
2. Loosen the drain plug and drain water.
3. After draining the water, tighten the drain plug.
4. Operate the priming pump on the fuel filter several times and check for fuel leakage.
5. Check the water separator indicator light. It should be off.
Except EURO III model
RTW 46ASH002901
For EURO III model
RTW 46ASH000501
Air Bleeding
1. Operate the priming pump until strong resistance is felt.
2. W ait 1 minute, and operate the priming pump until strong resistance is felt.
3. Once more wait, and operate the priming pump until strong resistance is felt.
4. Turn the ignition switch to the "ON" position. W ait until the glow indicator lamp turns off.
5. Turn the ignition switch to the "START" position and crank the engine until it starts.
6. If the engine does not start, repeat Step 3 - 5.
7. Allow the engine to idle for 3 minutes to bleed air completely form the fuel system and check for fuel
leakage.
Note:
Insufficient air bleeding may cause the Diagnostic
Trouble Code (DTC) store or improper engine
performance.
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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.
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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.
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ISUZU KB P190 2007
6A – 38 ENGINE MECHANICAL
6. Front propeller shaft (for 4x4 model)
Remove the spline yoke flange bolt at the transfer output
shaft.
Do not allow the spline yoke to fall away from the front
propeller shaft.
If the spline yoke should fall away from the front propeller
shaft, align the setting marks on the spline yoke and the
propeller shaft to reassemble the two marks. The setting
marks are punched circles approx. 3mm (0.12 in) in
diameter.
7. Clutch slave cylinder (for M/T model)
8. ATF pipe (for A/T model)
9 Shift control cable (for A/T model)
10. Transmission sensor harness Remove the vehicle speed sensor connector, inhibitor
switch connector (A/T), ATF temperature sensor
connector, back up light switch connector (M/T) from
transmission.
11. Breather hose (for A/T model)
12. Transmission shift lever (for M/T model) Remove the shift lever from the floor.
13. Transfer shift lever (for 4x4 model) Remove the shift lever from the floor.
14. Transmission member 1) Support the transmission with the transmission jack.
2) Remove the transmission member mounting bolts fixing the transmission member to the chassis frame.
15. Torque converter bolt (for A/T model) 1) Remove the under cover under the torque converter housing.
2) Rotate the flywheel by using tire lever or some other tool, and then remove the torque converter bolts.
16. Transmission coupling bolt 1) Support the engine with the garage jack.
2) Use the jack to slightly lower the transmission.
3) Remove the transmission coupling bolts.
17. Transmission (and transfer) Separate the transmission (and transfer) from the
engine.Take care not to damage the transmission, the
engine, and their related parts..
F06R300007
P1010025
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ISUZU KB P190 2007
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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ISUZU KB P190 2007
6A – 68 ENGINE MECHANICAL
ROCKER ARM SHAFT AND ROCKER ARM
Rocker Arm Shaft Run-Out
1. Place the rocker arm shaft on a V-block.
2. Use a dial indicator to measure the rocker arm shaft central portion run-out.
If the run-out is very slight, correct the rocker arm shaft
run-out with a bench press. The rocker arm must be at cold
condition.
If the measured rocker arm shaft run-out exceeds the
specified limit, the rocker arm shaft must be replaced.
Rocker Arm Shaft Run-Out mm (in)
Limit
0.3 (0.012)
Rocker Arm Shaft Outside Diameter
Use a micrometer to measure the rocker arm fitting portion
outside diameter.
If the measured value is less than the specified limit, the rocker
arm shaft must be replaced.
Rocker Arm Shaft Outside Diameter mm (in)
Standard Limit
18.98–19.00 (0.747–0.748) 18.90 (0.744)
Rocker Arm Shaft and Rocker Arm Clearance
1. Use either a vernier caliper or a dial indicator to measure
the rocker arm inside diameter.
Rocker Arm Inside Diameter mm (in)
Standard Limit
19.010–19.030 (0.748–0.749) 19.100 (0.752)
2. Measure the rocker arm shaft outside diameter.
If the measured value exceeds the specified limit, replace
either the rocker arm or the rocker arm shaft.
Rocker Arm Shaft and Rocker Arm Clearance mm (in)
Standard Limit
0.01–0.05
(0.0004–0.0020) 0.20 (0.008)
015LX009
014RY00024 015LX008
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ISUZU KB P190 2007
ENGINE MECHANICAL 6A – 69
3. Check that the rocker arm oil port is free of obstructions. If necessary, use compressed air to clean the rocker arm
oil port.
Rocker Arm Correction
Inspect the rocker arm valve stem contact surfaces for step
wear (1) and scoring (2).
If the contact surfaces have light step wear or scoring, they
may be honed with an oil stone.
If the step wear or scoring is severe, the rocker arm must be
replaced.
CYLINDER BODY
Cylinder Body Upper Face Warpage
1. Remove the cylinder body dowel.
2. Remove the cylinder liner. Refer to "Cylinder Liner Replacement".
3. Use a straight edge (1) and a feeler gauge (2) to measure
the four sides and the two diagonals of the cylinder body
upper face.
If the measured values exceeds the limit, the cylinder body
must be replaced.
Cylinder Body Upper Face Warpage mm (in)
Standard Limit
0.05 (0.002) or less 0.20 (0.008)
Cylinder Body Height (H) (Reference) mm (in)
Standard
4JA1T(L), 4JA1TC : 244.945-245.055 (9.6435-9.6478)
4JH1TC : 269.945-270.055 (10.6277-10.6320)
4. Reinstall the cylinder liner. Refer to "Cylinder Liner Replacement".
5. Reinstall the cylinder body dowel.
014RY00024
012R100001
012RY00009 014RY00023
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ISUZU KB P190 2007
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