1998 ISUZU TROOPER Remove engine

6A±45
ENGINE MECHANICAL

Apply sealant (TB1207B or equivalent) to the oil
pump mounting surface.

The oil pump assembly must be installed within 5
minutes after sealant application before the sealant
hardens.

Apply engine oil to oil seal lip.

Install oil pump in the cylinder block and tighten
fixing bolts to the specified torque.
Torque : 25 N´m (2.5 Kg´m/18 lb ft)
051RW002
Legend
(1) Around Bolt Holes
(2) Around Dowel Pin
051RW001
9. Install oil strainer with O-ring, tighten to the specified
torque.
Torque : 25 N´m (2.5 Kg´m/18 lb ft)
10. Install oil pipe with O-ring, tighten fixing bolts to the
specified torque.
Torque : 25 N´m (2.5 Kg´m/18 lb ft)11. Install crankcase.

Remove oil on crankcase mounting surface and dry
the surface.

Properly apply a 4.5 mm (0.7 in) wide bead of
sealant (TB1207C or equivalent) to the crankcase
mounting surface. The bead must be continuous.

The crankcase must be installed within 5 minutes
after sealant application before the sealant
hardens.

Tighten fixing bolts to the specified torque.
Torque : 10 N´m (1.0 Kg´m/89 lb in)
013RW010
013RW004
12. Install oil pan

Remove oil on oil pan mounting surface and dry the
surface.

Properly apply a 4.5 mm (0.7 in) wide bead of
sealant (TB1207C or equivalent) to the oil pan
mounting surface. The bead must be continuous.

The oil pan must be installed within 5 minutes after
sealant application to prevent premature hardening
of sealant.

6A±47
ENGINE MECHANICAL
Rear Oil Seal
Removal
1. Remove transmission assembly.

Refer to removal procedure for Transmission
section in this manual.
2. Remove flywheel.
3. Remove rear oil seal using a seal remover.
NOTE: Take care not to damage the crankshaft or oil seal
retainer when removing oil seal.
Installation
1. Apply engine oil to oil seal lip and install oil seal using
5±8840±2286±0.
015RS017
2. Install flywheel.

Clean tapped holes in the crankshaft.

Remove oil on the crankshaft and flywheel
mounting surface.

Tighten fixing bolts to the specified torque.
NOTE: Do not reuse the bolts and do not apply oil or
thread lock to the bolts.
Torque : 54 N´m (5.5 Kg´m/40 lb ft)
015RS018
3. Install transmission.

See Transmission section in this manual.
CAUTION: W h e n assembling the engine and
transmission, confirm that dowels have been
mounted in the specified positions at the engine
side. Take care that dowel positions are different
between the manual transmission and the automatic
transmission.
Otherwise, the transmission may be damaged.
012RS009

6A±48
ENGINE MECHANICAL
Engine Assembly
Removal
035RW027
1. Disconnect battery ground and positive cable.
2. Remove battery.
3. Make alignment mark on the engine hood and hinges
before removal in order to return the hood to original
position exactly.
4. Remove engine hood.
5. Drain radiator coolant.
6. Disconnect accelerator cable and automatic cruise
control cable from throttle valve on common
chamber.
7. Disconnect air duct with air cleaner cover.
8. Remove air cleaner assembly.
9. Disconnect canister vacuum hose.
10. Disconnect vacuum booster hose.
11. Disconnect three engine harness connectors.
12. Disconnect harness connector to transmission (left
front side of engine compartment), disconnect shift
on the fly harness connector from front side of front
axle and remove transmission harness bracket from
engine left side.
13. Disconnect ground cable between engine and frame.
14. Disconnect bonding cable connector on the back of
right dash panel.
15. Disconnect bonding cable terminal on the left bank.
16. Disconnect starter harness connector from starter.
17. Disconnect generator harness connector from
generator.
18. Disconnect coolant reserve tank hose from radiator.
19. Remove radiator upper and lower hoses.
20. Remove upper fan shroud.
21. Remove cooling fan assembly four fixing nuts, then
the cooling fan assembly.
22. Move drive belt tensioner to loose side using wrench
then remove drive belt.23. Remove power steering pump fixing bolts, then
power steering pump. Place the power steering pump
along with piping on the body side.
24. Remove air conditioning compressor fixing bolts from
bracket and place the compressor along with piping
on the body side.
25. Remove O
2 sensor harness connectors from exhaust
front pipe.
26. Remove three exhaust pipe fixing nuts from each
bank.
27. Remove two exhaust pipe fixing nuts from each
exhaust pipe, then move exhaust pipe to rear side of
vehicle.
28. Remove flywheel dust covers.
29. Disconnect two heater hoses from engine.
30. Disconnect fuel hoses from right side of transmission.
CAUTION: Plug fuel pipes on engine side and fuel
hoses from fuel tank.
31. Remove transmission assembly. Refer to
Transmission section in this manual.
32. Support the engine by engine hoist.
33. Remove two left side engine mount fixing bolts from
engine mount on chassis side.
34. Remove two right side engine mount fixing bolts from
engine mount on chassis side.
35. Remove engine assembly.
Installation
CAUTION: W h e n assembling the engine and
transmission, confirm that dowels have been
mounted in the specified positions at the engine
side. Take care that dowel positions are different
between the manual transmission and the automatic
transmission.

6A±52
ENGINE MECHANICAL
Cylinder Head
Cylinder Head and Associated Parts
011RW008
Legend
(1) Spark Plug
(2) Cylinder Head Bolt
(3) Camshaft Drive Gear Pulley Fixing Bolt
(4) Camshaft Drive Gear Pulley
(5) Camshaft Bracket Fixing Bolt
(6) Camshaft Bracket
(7) Camshaft Exhaust(8) Camshaft Intake
(9) Retainer Fixing Bolt
(10) Retainer Assembly
(11) Tappet with Shim
(12) Split Collar
(13) Valve Spring and Spring Upper Seat
(14) Valve
Disassembly
NOTE:

During disassembly, be sure that the valve train
components are kept together and identified so that
they can be reinstalled in their original locations.
Before removing the cylinder head from the engine
and before disassembling the valve mechanism,
perform a compression test and note the results.
1. Remove camshaft drive gear pulley fixing bolt (3),
then pulley (4).

6A±53
ENGINE MECHANICAL
2. Remove camshaft bracket fixing bolt (5), camshaft
bracket (6), then camshaft exhaust (7), and intake
side (8).
3. Remove tappet with shim (11).
4. Use the 5±8840±2446±0 valve spring compressor
and 5±8840±2547±0 valve spring compressor
adapter to remove the split collar (12), valve spring
with upper seat (13) and valve (14).
014RW042
5. Remove spark plug (1).
CAUTION: Do not remove the spark plugs when the
head and plugs are hot. Clean dirt and debris from
spark plug recess areas before removal.
Clean
Cylinder head
Carefully remove all varnish, soot and carbon from the
bare metal. Do not use a motorized wire brush on any
gasket sealing surface.
Inspection and Repair
1. Cylinder head gasket and mating surfaces for leaks,
corrosion and blow±by. If the gasket has failed,
determine the cause.
± Insufficient torque on head bolts.
± Improper installation
± Loose or warped cylinder head
± Missing dowel pins
± Warped case surface
2. Cylinder head for cracks, especially between valve
seats and in the exhaust ports.3. Cylinder head deck for corrosion, sand particles in
head and porosity.
CAUTION:

Do not attempt to weld the cylinder head. Replace
it.

Do not reuse cylinder head bolts.
4. Cylinder head deck, common chamber and exhaust
manifold mating surfaces for flatness. These
surfaces may be reconditioned by milling. If the
surfaces are ªout of flatº by more than specification,
the surface should be ground to within specifications.
Replace the head if it requires machining beyond the
repairable limit.
Head surface and manifold surface
Standard: 0.05 mm (0.002 in) or less
Warpage limit: 0.2 mm (0.0079 in)
Maximum Repairable limit: 0.2 mm (0.0079 in)
Head height
Standard height : 133.2 mm (5.2441 in)
Warpage limit : 0.2 mm (0.0079 in)
Maximum Repairable limit : 133.0 mm (5.2362 in)011RW019
5. Water jacket sealing plugs seating surfaces.
Reassembly
1. Install Spark plug and tighten all the spark plugs to
specified torque.
Torque: 18 N´m (1.8 Kg´m/13 lb ft)
2. Tighten sub gear setting bolt.
1. Use 5±8840±2443±0 gear spring lever to turn sub
gear to right direction until the M5 bolt aligns with
the hole between camshaft driven gear and sub
gear.

6A±56
ENGINE MECHANICAL
Valve Spring, Oil Controller, Valve, Valve Guide
Valve Spring, Oil Controller, Valve, Valve Guide and Associated Parts
014RW039
Legend
(1) Camshaft Bracket Fixing Bolts
(2) Camshaft Assembly Inlet
(3) Camshaft Assembly Exhaust
(4) Shim
(5) Tappet
(6) Split Collar(7) Spring Upper Seat
(8) Valve Spring
(9) Oil Controller
(10) Spring Lower Seat
(11) Valve Guide
(12) Valve
Disassembly
1. Remove camshaft bracket fixing bolts (1).
2. Remove camshaft assembly (intake).3. Remove camshaft assembly (Exhaust side).
4. Remove shim (4) and tappet (5).

6A±57
ENGINE MECHANICAL
5. Use 5±8840±2446±0 valve spring compressor and
5±8840±2547±0 valve spring compressor adapter to
remove split collar.
014RW042
6. Remove valve spring.
7. Remove valve.
8. Remove oil controller and spring lower seat.
9. Remove the valve guide using the 5±8840±2442±0
valve guide replacer.
Inspection and Repair
Valve Spring
CAUTION: Visually inspect the valve springs and
replace them if damage or abnormal wear is evident.
1. Measure the free height of the springs. The springs
must be replaced if the free height is below the
specified limit.
Standard : 44.6 mm (1.7559 in)
Limit : 43.6 mm (1.7165 in)
014RS004
2. Measure the valve spring squareness with a steel
square and replace the valve springs if the measured
value exceeds the specified limit.
Limit : 2 mm (0.0787 in)
014RS005
3. Using a spring tester to compress the springs to the
installed height, measure the compressed spring
tension, and replace the springs if the measured
tension is below the specified limit.
At installed height: 35.0 mm (1.38 in)
Standard: 196 N (44 lb)
Limit: Less than 181 N (41 lb)
014RS006
Valve Guide
CAUTION: Take care not to damage the valve seat
contact surface, when removing carbon adhering to
the valve head. Carefully inspect the valve stem for
scratchs or abnormal wear. If these conditions are
present, the valve and the valve guide must be
replaced as a set.

6A±59
ENGINE MECHANICAL
Limit: 39.47 mm (1.5539 in)
Exhaust
Standard: 39.30 mm (1.5472 in)
Limit: 39.45 mm (1.5531 in)
014RW047
2. Measure the valve seat contact width. Make the
necessary corrections if the seat contact surface is
damaged or rough or if the contact width wear
exceeds the limit.
Valve seat contact width
Standard: 1.1 mm (0.0433 in)
Limit: 1.7 mm (0.0669 in)
014RS011
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.
Valve contact surface angle: 45

014RS012
Valve Seat Insert Correction
1. Remove the carbon from the valve seat insert
surface.
2. Use a valve cutter 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 degree: 90

014RW059
3. Apply abrasive compound to the valve seat insert
surface.
4. Insert the valve into the valve guide.
5. Turn the valve while lapping it to fit the valve seat
insert.