removing engine ISUZU TROOPER 1998 Service Service Manual

6A2 Ð 16 4JG2-NA/4JG2-TURBO ENGINE
2) Measure the idler gear end play before removing the
idler gear.
NOTE:
Refer to the following items for details on the backlash
and end play measurement procedures.
Timing Gear Backlash Measurement
1) Set a dial indicator to the timing gear to measured.
Hold both the gear to be checked and the adjoining
gear stationary.
2) Move the gear to be checked as far as possible to
both the right and the left.
Take the dial indicator reading.
It the measured value exceeds the specified limit, the
timing gear must be replaced.
Idler Gear "A" End Play Measurement
Insert a feeler gauge between the idler gear and the thrust
collar to measure the gap and determine the idler gear
end play.
If the measued value exceeds the specified limit, the the
thrust collar must be replaced.
Standard
mm (in) Timing Gear Backlash
0.10-0.17 (0.0039-0.0067)Limit
0.30 (0.012)
11. Idle Gear
12. Injection Pump
1) Remove the six injection pump bracket bolts 1 from
the timing gear case.
Standard
mm (in) Idler Gear End Play
0.07 (0.0028)Limit
0.2 (0.0079)

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 17
2) Remove the injection pump rear bracket bolts 2 from
the injection pump bracket 3.
3) Remove the injection pump rear bracket bolts 4 and
the bracket 5 from the cylinder body.
4) Pull the injection pump along with the injection pump
timing gear free toward the rear of the engine.
NOTE:
Plug the injection pump delivery holder ports with the
shipping caps (or the equivalent) to prevent the entry of
foreign material.
13. Camshaft Timing Gear
1) Use a dial indicator to measure the camshaft end
play.
This must be done before removing the camshaft
gear.
If the camshaft end play exceeds the specified limit,
the thrust plate must be replaced.
2) Remove the camshaft timing gear bolt from the
camshaft.
NOTE:
Hold the camshaft stationaly to prevent the camshaft
from turning.
3) Use the universal puller 1 to pull out the camshaft
timing gear 2.
4) Remove the thrust plate 3.
14. Crank Shaft Gear
INSTALLATION
14. Crank Shaft Gear
1) Install the crankshaft gear.
2) Use the crankshaft gear installer 1 to install the
crankshaft gear 2.
The crankshaft gear timing mark ("X - X") must be
facing outward.
Crankshaft Gear Installer : 9-8522-0020-0
Standard
mm (in) Camshaft End Play
0.050-0.114 (0.0020-0.0044)Limit
0.2 (0.008)

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 37
PISTON, PISTON RING AND CONNECTING ROD
REMOVAL
1. Cylinder Head
·Refer to ÒCylinder HeadÓ removal in this sec-
tion.
2. Crankcase
·Refer to ÒCrankcaseÓ in this section.
3. Connecting Rod Bearing Cap
·Before removing the bearing cap, remove
carbon on the top of cylinder bore.
4. Piston, Piston Rings and Connecting Rod
·Push piston and connecting rod out from the
top of cylinder bore.
INSTALLATION
4. Piston, Piston Rings and Connecting Rod
·Apply engine oil to cylinder bore, connecting
rod bearings and crank pins.
·In installing the piston, its front mark must face
the engine front side.
3. Connecting Rod Bearing Cap
·The bearing cap number must be same as
connecting rod number.
·Apply engine oil to the thread and sealing
surface of each nuts.
·Tighten nuts to the specified torque.

ENGINE MECHANICAL 6A – 3
SERVICE INFORMATION
MAIN DATA AND SPECIFICATION
Engine type Diesel, four cycle water cooled inline
Camshaft type DOHC
Number of cylinders 4
Bore x stroke (mm) 95.4 x 104.9
Total piston displacement (cc) 2999
Compression ratio (to 1) 19.0
For Europe : 18.5
Engine weight (dry) N (kg/lb) 2492 (254/560) (A/T)
For Europe : 2422 (247/545) (A/T)
2649 (270/593) (M/T)
For Europe : 2697 (275/606) (M/T)
Engine idling speed (Reference) RPM 720
Compression pressure kpa (kg/cm
2/psi)-rpm 3040 (31/441)-200
Firing order 1–3–4–2
VALVE SYSTEM
Intake valves open at: B.T.D.C. 3°
close at: A.B.D.C. 57.6°
Exhaust valves open at: B.B.D.C. 56.5°
close at: A.T.D.C. 5°
Valve clearance (at cold) mm (in)
intake: 0.15 (0.006)
exhaust: 0.25 (0.01)
Oil filter Full flow and bypass combined type
Oil capacity (Original factory fill or rebuilt engine) 9.0 liters (7.9 US quarts)
Oil capacity (Service change)
with filter change 6.0 liters (6.3 US quarts)
without filter change 5.0 liters (5.3 US quarts)
Oil cooler Water cooled type
Inter cooler Air cooled type
Turbocharger method
Control method Wastegate control
Lubrication Pressurized control
Cooling method Coolant cooled
Crankshaft
As tufftriding (Nitrizing treatment) is applied to increase
crankshaft strength, crankpins and journals should not
be reground.
Piston Cooling
An oiling jet device for piston cooling is provided in the
lubricating oil circuit from the cylinder block oil gallery
via a check valve.
Take care not to damage any oiling jet when removing
and installing piston and connecting assembly.
Fuel Injection System
The injection system is oil rail type.
Quick On Start 4 System
QOS4 preheating system which features a quick-on
glow plug with thermometer control of the glowing time
and the afterglow time function, is applied.

ENGINE MECHANICAL 6A – 33
CYLINDER HEAD COVER
REMOVAL
1. Disconnect battery ground cable.
2. Remove clip, remove air cleaner cover and air duct.
3. Remove intercooler assembly.
Refer to “Intercooler” in this manual.
4. Remove PCV hose.
5. Remove bolts which fix noise insulator cover then
remove noise insulator cover and insulator.
6. Remove high pressure oil pipe at cylinder head
side.
Take care when removing the injector oil pipe,
because sometimes, during removal, your hand
can be injured by the remaining high pressure oil.
INSTALLATION
1. Cylinder head cover.
1) Install the cylinder head cover gasket to cylinder
head cover.
2) The gasket must be set perfectly with no loose
areas.
3) Apply liquid gasket (TB1207B or equivalent) to
the rubber seal of the camshaft end, injector
harness gasket area and No. 1 camshaft
bracket.4) Tighten cylinder head cover fixing bolts to the
specified torque.
Torque : 9 N·m (0.9 kg·m/6.5 lb ft)
2. Fill with about 300 cc of engine oil from the high
pressure oil pipe installation port of the oil rail using
an oil rail filler. If assembled without filling the oil rail
with oil, the time for starting the engine will be
longer.
3. Install the high pressure oil pipe immediately and
tighten the sleeve nut to the specified torque.
Torque : 80 N·m (8.1 kg·m/57.9 lb ft)
1 7
2
3
4
5 6
010R200006
Legend
(1) Noise Insulator Cover
(2) Insulator
(3) Bolt(4) Oil Seal
(5) Gasket
(6) Cylinder Head Cover
(7) Bolt
3~52~32~33~5
3~5 1~2
012RW119

ENGINE MECHANICAL 6A – 41
CYLINDER HEAD
3
4
1
2
012RW096
Legend
(1) Glow Plug
(2) Plate
(3) Cylinder Head Bolt
(4) Cylinder Head
NOTE:
•During disassembly, be sure that the valve train
components are kept together and identified so that
they can be re-installed in their original locations.
•Before removing the cylinder head from the engine
and before disassembling the valve mechanism, do
a compression test and note the results.
DISASSEMBLY
1. Injector Assy
2. Glow Plug and Glow Plug Connector
3. Cylinder Head Assembly
•Refer to “Cylinder Head Gasket”
CLEAN
•Cylinder head
Carefully remove all varnish, soot and carbon on
the bare metal. Do not use a motorized wire brush
on any gasket sealing surface.
INSPECTION AND REPAIR
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is
discovered during inspection.
1. Cylinder head gasket and mating surfaces for
leaks, corrosion and blow-by. If the gasket has
failed, determine the cause;
–Improper installation
–Loosen or warped cylinder head
–Insufficient torque on head bolts
–Warped cylinder block surface

6A – 62 ENGINE MECHANICAL
3. Spring tension
1) Use a spring tester to compress the springs to
the installed height. Measure the compressed
spring tension.
2) Replace the springs if the measured tension is
below the specified limit.
Standard: 236.0 N (24 kg/53 lb)
Limit: 205.0 N (21 kg/46 lb)Valve Guide
CAUTION: Taking care not to damage the valve seat
contact surface, when removing carbon adhering to
the valve head.
Carefully inspect the valve stem for scratching or
abnormal wear. If these conditions are present, the
valve and the valve guide must be replaced as a set.
1. Valve Guide Clearance
1) Measure the valve stem diameter with a
micrometer.
If the valve stem diameter is less than the
specified limit, the valve and the valve guide
must be replaced as a set.
Diameter of Valve stem:Inlet
Standard: 6.959 – 6.977 mm (0.2740 – 0.2747 in)
Limit: 6.92 mm (0.2724 in)
Diameter of Valve stem:Exhaust
Standard: 6.952 – 6.97 mm (0.2737 – 0.2744 in)
Limit: 6.90 mm (0.2717 in)
2) Measure the inside diameter of the valve guide
with a micrometer.
3) Subtract the measured outer diameter of the
valve stem from the measured inner diameter of
the valve guide.
If the valve exceeds the specified limit, the valve
and the valve guide must be replaced as a set.
Inlet clearance
Standard: 0.023 – 0.053 mm (0.0009 – 0.0021 in)
Limit: 0.19 mm (0.0075 in)
Exhaust clearance
Standard: 0.03 – 0.063 mm (0.0012 – 0.0025 in)
Limit: 0.20 mm (0.0079 in)
014RS006
014RS007

ENGINE MECHANICAL 6A– 85
DISASSEMBLY
1. Cylinder Head Assembly
1) Refer to “Cylinder head” in this manual.
2. Crank Case Assembly
1) Refer to “Crank Case” in this manual.
3. Connecting Rod Bearing Cap
4. Piston and Connecting Rod
1) Remove carbon deposits from the upper portion
of the cylinder wall with a scraper before
removing the piston and connecting rod.
5. Piston Ring
Remove the piston rings with a piston ring
expander.
Arrange the removed piston rings in the cylinder
number order.
6. Piston Pin Snap Ring
1) Use a pair of pliers to remove the piston pin
snap rings.7. Piston Pin
1) Remove piston pin from piston assembly.
NOTE: Keep the parts removed from each cylinder
separate. All parts must be reinstalled in their original
positions.
8. Piston
9. Connecting Rod
INSPECTION AND REPAIR
PISTON AND PISTON RING
Pistons
Carefully clean away all the carbon adhering to the
piston head and the piston ring grooves.
NOTE: Never use a wire brush to clean the pistons.
Damage will result. Visually check each piston for
cracking, scoring, and other signs of excessive wear. If
any of the above conditions are present, the piston
must be replaced.
Piston Diameter
1. Measure the piston outside diameter with
micrometer at the piston grading position.
Piston Grading Position: 69.75 mm (2.7461 in)
from piston head
Piston Outside Diameter mm(in)
Grade Mark Outside Diameter
A 95.320 – 95.329 (3.7527 – 3.7531)
B 95.330 – 95.339 (3.7531 – 3.7535)
C 95.340 – 95.349 (3.7535 – 3.7539)
015RW082
015RW077
015LV014

ENGINE FUEL 6C – 15
HIGH PRESSURE OIL PUMP
REMOVAL
1. Disconnect battery ground cable.
2. Remove air cleaner cover and air duct
3. Intercooler assembly
Refer to “Intercooler” in this manual.
4. Remove high pressure oil pipe
5. Timing belt cover
Disconnect CMP sensor cable.
Remove CMP sensor bracket.
6. Tensioner
7. Timing Belt
8. Remove high pressure oil pump timing pulley
9. Remove crankshaft damper pulley
10. Remove timing gear case cover
11. Remove idle gear A
Before removing idle gear A, set two bolts to the
sub gear of idle gear A and turn it to align the teeth
of idle gear A main gear.
Then lock them by bolts as shown in the illustration.Legend
(1) Idle gear A sub gear
(2) Idle gear A main gear
(3) Bar
(4) Lock bolt
1
2
43
Legend
(1) O-Ring
(2) High Pressure Oil Pump Assembly
(3) Nut
(4) O-Ring
040RW007
4 1
2
3
014RW177

6E±153 4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
10. To avoid backprobing the VSS and possibly
damaging a seal or terminal, the VSS output can be
tested at the point where the transmission harness
connected to the engine harness. The green 16-way
connector is adjacent to a blue 16-way connector,
and it can be easily accessed by removing the air
cleaner assembly. The green 16-way connector is
separated, and battery voltage is applied to the VSS
through the yellow wire at one corner of the
connector. The VSS output can be monitored with a
DVM connected to the blue wire with a black tracer.
The two wires are next to each other in the 16-way
connector . The test connections are made on the
transmission side of the connector, the side that is
not clipped to the body sheetmetal.11. The speedometer-to-ECM VSS signal wire is
spliced to a wire leading to the cruise control
module. If a short to ground or voltage is found
between the ECM and speedometer, it could be
located between the splice and the cruise control
module.
DTC P0502 ±VSS No Signal

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Does the speedometer work?ÐGo to Step 10Go to Step 3
31. Disconnect the VSS connector.
2. Ignition ªON.º
3. Using a test light to battery +, probe the connector
ground wire.
Did the light illuminate?
ÐGo to Step 5Go to Step 4
4Repair the sensor ground.
Is the action complete?
ÐVerify repairÐ
51. Ignition ªON,º sensor disconnected.
2. Using a DVM, measure at the VSS connector
between ground and voltage supply.
Was the measurement near the specified value?
Battery
voltage
Go to Step 7Go to Step 6
6Repair the open or short to ground which may have
blown the meter fuse.
Is the action complete?
ÐVerify repairÐ
71. Ignition ªON,º VSS disconnected.
2. Using a DVM, measure at the VSS connector
between ground and the blue/black wire from the
speedometer.
Was the measurement near the specified value?
7.5-8 VGo to Step 9Go to Step 8
8Check for an open or short circuit between the
speedometer and the VSS.
Was an open or short circuit located?
ÐVerify repairGo to Step 9
9Replace the VSS.
Is the action complete?
ÐVerify repairGo to Step 10
10Replace the speedometer.
Is the action complete?
ÐVerify repairGo to Step 11