1998 ISUZU TROOPER Remove engine

6A – 54 ENGINE MECHANICAL
15. High pressure oil pump
1) Remove oil pump gear fixing bolt then remove
oil pump.
Legend
(1) O-Ring
(2) High Pressure Oil Pump Gear
(3) Bolt
(4) Timing Mark
16. Remove balance shaft gear LH. and RH.
17. Remove crankshaft gear.
INSTALLATION
1. Crankshaft gear
1) Force key into the crankshaft and insert
crankshaft gear with the crankshaft gear key
groove set on the key.Legend
(1) Crankshaft Gear Installer
(2) Crankshaft Gear
2. Balance shaft gear
1) Install the balance shaft gear RH to balance
shaft, tighten center bolt to the specified torque.
Torque : 32 N·m (3.2 kg·m/23 lb ft)
2) Install thrust plate for balance shaft LH before
installing the balance shaft gear LH.
Torque : 25 N·m (2.5 kg·m/18 lb ft)
3) Install balance shaft gear LH to balance shaft,
tighten center bolt to the specified torque.
Torque : 32 N·m (3.2 kg·m/23 lb ft)
Legend
(1) Center Bolt
(2) Plate
(3) Balance Shaft Gear RH
(4) Timing Mark
4
GEAR:O/PUMP
IDLE GEAR A
1
2
3
040RW005
12
2
012RW066
3
4 2
1
014RW173

6A – 56 ENGINE MECHANICAL
Legend
(1) Bolt
(2) Retainer
(3) Idle Gear B
(4) Idle Gear B Shaft
(5) Align Mark
6. High pressure oil pump
1) Install O-ring on the high pressure oil pump.
2) Install the high pressure oil pump to the timing
gear case, tighten the nut to the specified
torque.
Torque: 20 N·m (2.0 kg·m/14.5 lb ft)
NOTE: Be sure to set O-ring completely.
Legend
(1) O-ring (large)
(2) High pressure oil pump
(3) Nut
(4) O-ring (small)7. High pressure oil pump
1) Install O-ring on the oil pump shaft with grease
and install the gear with the idle gear A timing
mark set at the oil pump gear timing mark.
2) Tighten center bolt to the specified torque.
Torque: 75 N·m (7.6 kg·m / 55 lb ft)
NOTE: Be sure to align timing marks with each other.
Legend
(1) O-ring
(2) High Pressure Oil Pump Gear
(3) Center Bolt
(4) Timing Mark
8. Remove lock from idle gear.
1) Remove lock bolt from idle gear A and remove
lock pin from idle gear C.
9. Timing gear case assembly
1) Clean fixing surface of timing gear case.
2) Install the gasket on the idle gear rear side end.
3) Apply liquid gasket to the timing gear case fitting
surface.
NOTE: Be sure to apply liquid gasket evenly.
4) Install timing gear case and tighten bolts to the
specified torque.
Torque: 20 N·m (2.0 kg·m / 14.5 lb ft)
NOTE: Must install within 5 minutes after applying liquid
gasket.
35
5
4
3
2
1
014R200008
1
2
43
040RW007
4
GEAR:O/PUMP
IDLE GEAR A
1
2
3
040RW005

6A – 60 ENGINE MECHANICAL
VALVE STEM SEAL, VALVE SPRING AND ADJUSTER
REMOVAL
1. Disconnect battery ground cable.
2. Drain engine coolant.
3. Remove the air duct from between air cleaner and
turbocharger.
4. Remove intercooler assembly.
Refer to “Intercooler” in this manual.
5. Remove oil level gauge guide assembly.
6. Disconnect PCV hose.
7. Disconnect EGR vacuum hose.
8. Disconnect harness connectors around the cylinder
head such as the injector, CMP sensor, MAP
sensor, EGR sensor, EVRV, IAT sensor, A/C
compressor, TP stepping motor, TP sensor and fuel
temperature sensor etc.
9. Remove A/C compressor assembly.
10. Remove A/C compressor bracket.
11. Remove generator assembly and take out drivebelt.
12. Remove heat protector, remove exhaust valve
assembly.
13. Remove water cooling hose and lubrication pipe for
turbocharger.
14. Remove turbocharger assembly.
15. Remove hose between thermostat and radiator.
16. Remove noise insulator cover of cylinder head.
NOTE: Do not damage injector harness.
17. Remove high pressure oil pipe.
18. Remove timing belt cover.
19. Remove CMP sensor bracket.
20. Remove timing belt tensioner then remove timing
belt.
21. Remove camshaft pulley.
22. Remove front plate.
23. Remove engine coolant pipe between cylinder
head and water pump.
1
2
3
4
5
6
9
10
7
8
011RW031
Legend
(1) Adjuster
(2) Tappet
(3) Split Collar
(4) Spring Seat Upper
(5) Valve Spring(6) Spring Seat Lower
(7) Valve Stem Seal
(8) Valve Guide
(9) Valve Seat
(10) Valve

ENGINE MECHANICAL 6A – 61
24. Remove fuel pipe between fuel pump and intake
manifold.
25. Remove fuel return pipe from rear of cylinder head.
26. Remove intake manifold assembly.
27. Disconnect glow plug harness and remove glow
plug.
28. Remove cylinder head cover.
29. Remove injector harness connector.
30. Disconnect harness connector from oil pressure
sensor and oil temperature sensor on the oil rail.
31. Remove injector harness assembly.
32. Remove injector clamp.
33. Remove injector is fixed bolts.
34. Remove injector assembly.
35. Remove oil rail.
36. Remove camshaft carrier assembly with camshaft.
37. Remove cylinder head assembly.
38. Disassemble valve spring according to the following
method.
1) Use valve spring compressor then remove split
collars.
2) Valve spring compressor: 5-8840-2441-0
NOTE: Put removed valve spring in order of cylinder
number.
39. Valve stem seal.
1) Use a screwdriver or pliers to remove valve
stem seal.
NOTE: Do not reuse removed valve stem seal.
INSPECTION AND REPAIR
Make the necessary adjustments, repairs and part
replacements if excessive wear or damage is
discovered during inspection.
Valve spring
CAUTION: Visually inspect the valve springs and
replace them if damage or abnormal wear is
evident.
1. Free height
1) Measure the free height of the springs. The
springs must be replaced if the height is below
the specified limit.
Standard: 45.85 mm (1.8051in)
Limit: 43.9 mm (1.7283 in)
2. Squareness
1) Measure the valve spring squareness with a
steel square.
2) Replace the valve springs if the measured value
exceeds the specified limit.
Limit: 1.6 mm (0.063 in)
014rw042
014rs004
014rs005

ENGINE MECHANICAL 6A – 63
Valve Guide Replacement
1. Using the special tool, drive out the valve guide
from the combustion chamber side.
Valve guide replacer: 9-8523-1212-0
2. Apply engine oil to the outside of the valve guide.
Using the special tool, drive in a new valve guide
from cylinder head upper face side, and check the
valve guide height.
Valve guide replacer: 9-8523-1212-0
Height: 8.0 mm (0.315 in)
NOTE: If the valve guide has been removed, both the
valve and the valve guide must be replaced as a set.
Valve Thickness
1. Measure the valve thickness.
2. If the measured value is less than the specified
limit, the valve and the valve guide must be
replaced as a set.
Inlet
Standard: 1.2 mm (0.0472 in)
Limit: 1.1 mm (0.0433 in)
Exhaust
Standard: 1.2 mm (0.0472 in)
Limit: 1.1 mm (0.0433 in)
Contact surface angle on valve seat on
valve
1. Measure contact surface angle on valve seat.
2. If the measured value exceeds the limit, replace
valve, valve guide and valve seat as a set.
Standard: 68°
011RW001
012RW052
012RW060
014RW018

6A – 64 ENGINE MECHANICAL
Valve Depression
1. Measure the valve stem height from the upper
surface of the cylinder head as shown in the
illustration.
Standard:
Intake side 35.59 mm (1.4012 in)
Exhaust side 35.49 mm (1.3972 in)
Limit:
Intake side 35.74 mm (1.4071 in)
Exhaust side 35.64 mm (1.4031 in)
Legend
(1) Intake Side
(2) Exhaust Side
Valve Contact Width
1. Check the valve contact faces for roughness and
unevenness. Make the valve contact surfaces
smooth.
2. Measure the valve contact width.
If the measured value exceeds the specified limit,
the valve seat insert must be replaced.
Inlet
Standard: 2.1 mm (0.0827 in)
Limit: 2.6 mm (0.1024 in)
Exhaust
Standard: 2.0 mm (0.0787 in)
Limit: 2.5 mm (0.0984 in)
Valve Seat Insert Replacement
Valve Seat Insert Removal
1. Arc weld the entire inside circumference of the
valve seat insert.
2. Allow the valve seat insert to cool for a few minutes.
This will invite contraction and make removal of the
valve seat insert easier.
3. Use a screwdriver to pry the valve seat insert free.
Take care not to damage the cylinder head.
4. Carefully remove carbon and other foreign material
from the cylinder head insert bore.

011RW044
014RS015

ENGINE MECHANICAL 6A – 65
Valve Seat Insert Installation
1. Carefully place the attachment (1) (having a smaller
outside diameter than the valve seat insert) on the
valve seat insert (2).
Legend
(1) Attachment
(2) Valve Seat Insert
(3) Bench Press
NOTE: The smooth side of the attachment must contact
the valve seat insert.
2. Use a bench press (3) to gradually apply pressure
to the attachment and press the valve seat insert
into place.
Note: Do not apply an excessive amount of pressure
with the bench press. Damage to the valve seat insert
will result.
Valve Seat Insert Correction
1. Remove the carbon from the valve seat insert
surface.
2. Use a valve cutter (15°, 45°and 75°blades) to
minimize scratches and other rough areas. This will
bring the contact width back to the standard value.
Remove only the scratches and rough areas. Do
not cut away too much. Take care not to cut away
unblemished areas of the valve seat surface.
Valve Seat Angle: 45°NOTE: Use an adjustable valve cutter pilot.
Do not allow the valve cutter pilot to wobble inside the
valve guide.
3. Apply abrasive compound to the valve seat insert
surface.
4. Insert the valve into the valve guide.
5. Turn the valve while tapping it to fit the valve seat
insert.
6. Check that the valve contract width is correct.
7. Check that the valve seat insert surface is in
contact with the entire circumference of the valve.
3
2 1
012RW055
150°
90°
30°
012RW056
014RS014

ENGINE MECHANICAL 6A – 67
VALVE CLEARANCE ADJUSTMENT
NOTE:
1. Valve clearance should be inspected and adjusted
while the engine is cool.
2. The tightening of the camshaft bearing cap and
camshaft carrier assembly should be checked
before inspecting and adjusting valve clearance.
INSPECTION
1. Remove cylinder head noise insulator cover and
cylinder head cover.
Refer to “Cylinder Head” in this manual.
2. Disconnect all harness connecters of the injector
and remove harness assembly.
3. Drain oil from oil rail assembly.
4. Remove injector clamp nuts and fixing bolts to take
out injector assembly.
5. Loosen oil rail bolts, remove oil rail assembly.
6. Set cylinder No.1 to the TDC at the compression
stroke. Make sure that there is play in cylinder No.1
tappets on inlet and exhaust sides and that there is
no play in cylinder No.4 tappets.
7. Measure valve clearance at No.1 TDC (Refer to the
black circles indicated in the illustration).
Standard Valve clearance:
Intake valve: 0.15 mm (0.0059 in) ± 0.05 mm (0.0020 in)
Exhaust valve: 0.25 mm (0.0098 in) ± 0.05 mm (0.0020 in)
8. Turn the crankshaft one turn to set No.4 cylinder
TDC at the compression stroke.
9. Measure valve clearance at No.4 TDC (Refer to the
black circles indicated in the illustration).
Standard Valve clearance:
Intake valve: 0.15 mm (0.0059 in) ± 0.05 mm (0.0020 in)
Exhaust valve: 0.25 mm (0.0098 in) ± 0.05 mm (0.0020 in)
10. If measured value is outside standard value,
readjust the valve clearance.
ADJUSTMENT
For valve clearance adjustment, follow the procedure
given below.
1. Set cylinder No.1 or No.4 to the TDC at the
compression stroke.
Set the valve clearance adjusting tool on the tappet
requiring adjustment.
After making sure of the correct setting of the
special tool, depress the tappet by turning the bolt.
Valve Clearance Adjusting Tool: 5-8840-2590-0
NOTE: Before depressing the tappet, set the tappet
notch in the direction where adjuster can be easily
taken out.
2. Take out the adjuster using a small screw driver and
finger magnet.
No.1
FtNo.2No.1 TDC
No.3 No.4EXH
IN
011RW045
No.1
FtNo.2No.4 TDC
No.3 No.4EXH
IN
011RW046
014RW150