Remove engine ISUZU TROOPER 1998 Service Repair Manual

6G±12
ENGINE LUBRICATION
Oil Pump Oil Seal
Removal
1. Disconnect battery ground cable.
2. Drain engine oil.
3. Remove crankshaft pulley.

Refer to removal procedure for Crankshaft Pulley in
this manual.
4. Remove timing belt.

Refer to removal procedure for Timing Belt in this
manual.
5. Remove timing pulley from crankshaft.
6. Remove oil pump oil seal using a sealer puller.
NOTE: Take care not to damage sealing surfaces of oil
pump and crankshaft when removing oil seal.
Installation
1. Install oil pump oil seal, apply engine oil to oil seal lip,
then install oil seal using 5±8840±2287±0 installer.
015RS001
2. Install timing pulley to crankshaft.
3. Install timing belt.

Refer to installation procedure for Timing Belt in this
manual.
4. Install crankshaft pulley.

Refer to installation procedure for Crankshaft
Pulley in this manual.
5. Refill engine oil until full level.

6G±13 ENGINE LUBRICATION
Oil Filter
Removal
1. Disconnect battery ground cable.
2. Drain engine oil.
3. Remove oil filter using 5-8840-0203-0 filter wrench.
Installation
1. Clean filter fitting surface and apply small amount of
engine oil to sealing surface.
2. Install oil filter cartridge by hand until it comes in
contact with sealing surface then rotate additional 2/3
turn to tighten using 5-8840-0203-0 filter wrench.
050RW001
Legend
(1) Oil Pump
(2) Oil Filter
(3) Oil Gallery
(4) From Filter
(5) To Filter
3. Fill engine oil until full level on dipstick.
4. Reconnect battery ground cable.

6H±2
ENGINE SPEED CONTROL SYSTEM
Accelerator Pedal Control Cable
Removal
1. Loosen the adjusting nut(5) on the cable bracket
mounted on the common chamber.
2. Remove cable clip(3).
3. Disconnect accelerator pedal (AP) control cable(6).
(on throttle valve side)
4. Disconnect AP control cable(1). (on AP pedal(7) side)
5. Remove molding cap(2).
6. Remove AP control cable(4).
101RW001
Inspection
Check the following items, and replace the control cable if
any abnormality is found:

The control cable should move smoothly.

The control cable should not be bent or kinked.

The control cable should be free of damage and
corrosion.
Installation
1. Install AP control cable(4).
2. Install molding cap(2).
3. Connect AP control cable(1). (on AP side)
4. Connect AP control cable(6). (on throttle valve side)
5. Install cable clip(3).
6. Install adjusting nut(5).
101RW001
Adjustment
1. Loosen adjusting nut and lock nut.
2. Pull outer cable while closing fully the throttle valve.
3. Tighten adjusting nut and lock nut temporarily.
4. Loosen adjusting nut by three turns and tighten lock
nut.
Then, manually operating the throttle valve, make
sure that the valve lever returns up to the stopper
screw.
If it does not reach the stopper screw, repeat from
step 1.
035RW004
Legend
(1) Clearance
(2) Lock Nut
(3) Adjusting Nut

00 Ð 28 SERVICE INFORMATION
3. Remove the element from the solution and rinse it well
with running water.
Water pressure must not exceed 274 Kpa (2.8 kg/cm
2/40
Psi)
4. Dry the element in a well ventilated area.
An electric fan will hasten drying.
NOTE:
Do not use compressed air or an open flame to dry the
element quickly. Damage to the element will result.
It will usually take two or three days for the element to dry
completely. Therefore, it is a good idea to have a spare on
hand to use in the interim.
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 by turning it counterclockwise
with the filter wrench.
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 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 1
and 1/4 turns.
Filter Wrench: 5-8840-0200-0
8. Check the engine oil level and replenish to the specified
level if required.
0.7 (0.62/0.74)
lit(Imp qt / US qt) Replenishment Engine Oil
9. Start the engine and check for oil leakage from the main
oil filter.

SERVICE INFORMATION 00 Ð 29
FUEL SYSTEM
Fuel Filter
Replacement Procedure
1. Loosen the used fuel filter by turning it counterclock-
wise with the filter wrench.
Filter Wrench: 5-8840-0253-0 (J-22700)
2. Remove the level sensor from the filter by turning it
counterclockwise with a wrench.
3. Install the level sensor to the new fuel filter with a
wrench.
5. Apply a light coat of engine oil to the O-ring.
6. Turn in the fuel filter until the sealing face comes in
contact with the O-ring.
7. Turn in the fuel filter an additional 2/3 of a turn with a
filter wrench.
Filter Wrench: 5-8840-0253-0 (J-22700)
8. Loosen the bleeder plug on the injection pump overflow
valve.
9. Operate the priming pump until fuel begins to flow from
the fuel filter.
10. Retighten the bleeder plug.
11. Operate the priming pump several times and check for
fuel leakage.
NOTE:
The use of an ISUZU genuine fuel filter is strongly recom-
mended.
13 (1.3/9)
N·m (Kg·m/lb·ft) Level Sensor Torque
4. Clean the filter cover fitting faces.
This will allow the new fuel filter to seat properly.

SERVICE INFORMATION 00 Ð 31
Remove the radiator filler cap only when absolutely neces-
sary.
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 pres-
sure.
Radiator Cap Inspection
The radiator filler cap is designed to maintain coolant pres-
sure in the cooling system at 1.05 kg/cm
2 (15 psi/103 kPa).
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
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.
82 (180)
°C(°F) Thermostat Initial
Opening Temperature
4. Check the thermostat full opening temperature.
1.0 – 3.9 (0.01 – 0.04/0.14 – 0.57)
Negative Valve (Reference)Kpa (Kg/cm2 / Psi)
90 (194)
°C(°F) Thermostat Full
Opening Temperature
10 (0.39)
mm(in) Valve Lift at Fully Open Position
196 (2/28.45)
Testing Pressure Kpa (Kg/cm2 / Psi)
93.3 – 122.7 (0.95 – 1.25/13.5 –17.8)
Pressure Valve
Kpa (Kg/cm2 / Psi)

SERVICE INFORMATION 00 Ð 33
ENGINE CONTROL
Idling Speed Adjustment
1. Set the vehicle parking brake and choke the drive wheels.
2. Place the transmission in neutral.
3. Start the engine and allow it to warm up.
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.
Fast Idling Speed Adjustment
1. Loosen the fast idle actuator lock nut 1 .
2. Adjust the fast idling speed by turning the adjusting
screw 2 .
3. Tighten the lock nut 1 .
4. Connect the vacuum hose to the fast idle actuator.
5. Connect the other vacuum hose to the vacuum switch-
ing valve.750 (4JG2-NA)/720 (4JG2-T)
rpm Engine Idling Speed
Idling Speed Adjustment
1. Loosen the idling set screw lock nut 1 on the injection
pump idling set bolt.
2. Adjust the idling speed to the specified range by turning
the idling set bolt 2.
3. Lock the idling set bolt with the idling set screw lock nut.
4. Check that the idling control cable is tight (free of slack).
If required, remove the slack from the cable.
Fast Idling Speed Inspection
1. Set tachometer to the engine.
2. Disconnect the vacuum hose from the fast idle actuator
1 on the injection pump.
3. Disconnect the other vacuum hose 2 from the vacuum
switching valve 3 and connect it to the fast idle actuator
1 .
The vacuum line will now be connected directly from
the vacuum pump 4 to the fast idle actuator.
4. Check the engine fast idling speed.
If the engine idling speed is outside the specified range,
it must be adjusted.
850 – 950
rpm Fast Idling Speed

00 Ð 34 SERVICE INFORMATION
Accelerator Control
Accelerator Control Cable Adjustment
1. Loosen the accelerator cable clamp bolt 1 .
2. Check that the idling control knob on the instrument
panel is in the engine idling position.
3. Hold the accelerator lever 2 in the fully closed position
and stretch the control cable 3 in the direction indi-
cated by the arrow to remove any slack.
Accelerator Pedal Adjustment
1. Depress the accelerator pedal and hold it.
2. Use the stopper bolt 1 to adjust the clearance between
the stopper bolt end and the accelerator pedal lower
face 2 .
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.
2. Check the rocker arm shaft bracket nuts for looseness.
Tighten any loose rocker arm shaft bracket nuts before
adjusting the valve clearance.
3. 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 com-
pression stroke.
54 (5.5/40)
N·m(Kg·m/lb·ft) Rocker Arm Shaft
Bracket Nut Torque2 – 5 (0.08 – 0.20)
mm(in) Accelerator and
Stopper Bolt Clearance

SERVICE INFORMATION 00 Ð 35
Adjust the No. 1 or the No. 4 cylinder valve clearances while
their respective cylinders are at TDC on the compression
stroke.
0.4 (0.016)
mm(in) Valve Clearance (At Cold)
4. Loosen each valve clearance adjusting screw as shown
in the ilustration.
5. Insert a feeler gauge of the appropriate thickness be-
tween the rocker arm and the valve stem end.
6. Turn the valve clearance adjusting screw until a slight
drag can be felt on the feeler gauge.
7. Tighten the lock nut securely.
8. Rotate the crankshaft 360°.
9. Realign the crankshaft damper pulley TDC notched line
with the timing pointer.
10. Adjust the clearances for the remaining valves as shown
in the illustration.
INJECTION TIMING ADJUSTMENT
1. Set the No. 1 cylinder to Top Dead Center.
2. Remove injector pump distributor head plug.
3. Cancel Wax CSD with the handle of a screw driver.
4. Fit a dial gauge and set lift to 1 mm.
5. Set crankshaft damper pulley Top Dead Center mark
about 45° before Top Dead Center from the pointer.
6. Set dial gauge in the ÒOÓ position.
Measuring device : 5-8840-0145-0
7. Turn the crankshaft a little rightwise and leftwise and
see it the pointer is stable in the ÒOÓ position.
8. Turn the crankshaft in the normal direction and read the
measuring deviceÕs indication at TDC (4JG2-T) or 1°
ATDC (4JG2-NA).
9. 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.
¥ If injection timing will be advanced, move the injec-
tion pump toward the engine.
¥ If injection timing will be retarded, move the injec-
tion pump away from the engine.
Tighten the pump fixing nut, adjust bolt and pump distribu-
tor head plug to the specified torque.
19(1.9/13)
N·m(Kg·m/lb·ft) Pump Fixing Bolt
0.5 (0.02)
mm(in) Starting Timing

00 Ð 36 SERVICE INFORMATION
CAUTION
¥ When installing the distributor head plug, be sure to use
new copper washer.
COMPRESSION PRESSURE MEASURE-
MENT
1. Start the engine and allow it to idle until the coolant
temperature reaches 70 Ð 80°C (158 Ð 176°F).
2. Remove the following parts.
* Glow plugs
* Fuel cut solenoid connector
* QOS (Quick-On Start System) fusible link wire at the
connector.
3. Set the adapter and compression gauge to the No. 1
cylinder glow plug hole.
Compression Gauge
(with Adapter): 5-8840-2675-0
Adapter: 5-8531-7002-0
5. Repeat the procedure (Steps 3 and 4) for the remaining
cylinders.
If the measured value is less than the specified limit,
refer to ÒTroubleshootingÓ in this Manual.
17 (1.7/12)
N·m(Kg·m/lb·ft) Injection Pump
Distributor Head Plug
4. Turn the engine over with the starter motor and take the
compression gauge reading.
40(4.1/30)
N·m(Kg.m/lb·ft) Adjust Bolt
Kpa (Kg/cm2 / Psi)
Standard Limit
2940 (30/426) 2157 (22/313) Compression Pressure at 200 rpm