ISUZU TROOPER 1998 Service Repair Manual

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±46
ENGINE MECHANICAL

Tighten fixing bolts to the specified torque.
Torque : 25 N´m (2.5 Kg´m/18 lb ft)
013RW003
013RW002
13. Install timing belt.

Refer to installation procedure for Timing Belt in this
manual.
14. Install engine assembly.

Refer to installation procedure for Engine in this
manual.

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±49
ENGINE MECHANICAL
If the engine is assembled in the condition that the
dowels have not been mounted in the specified posi-
tions, the transmission may be damaged the trans-
mission.
012RS009
1. Install engine assembly. Tighten engine mount fixing
bolts to frame to the specified torque.
Torque: 41 N´m (4.2 Kg´m/30 lb ft)
2. Reconnect fuel hose to fuel pipe on engine.
3. Install transmission assembly. Refer to Transmission
section in this manual.
4. Reconnect two heater hoses to engine.
5. Install flywheel dust covers.
6. Install exhaust pipe and temporally tighten two (each
bank) rear exhaust flange nuts then tighten three stud
nuts (each bank) between exhaust manifold and
exhaust pipe, finally tighten rear side nuts to the
specified torque.
Torque:
Nuts: 43 N´m (4.4 Kg´m/32 lb ft)
Stud nuts: 67 N´m (6.8 Kg´m/49 lb ft)
150RW061
Legend
(1) Exhaust Front Pipe RH
(2) O
2 Sensor (for IGM)
150RW062
Legend
(1) Exhaust Front Pipe LH
7. Reconnect O2 sensor connector.
8. Install cooling fan assembly and tighten bolts/nuts to
the specified torque.
Torque : 22 N´m (2.2 Kg´m/16 lb ft) for fan pulley
and fan bracket.
Torque : 10 N´m (1.0 Kg´m/88.5 lb in) for fan and
clutch assembly.

6A±50
ENGINE MECHANICAL
9. Install air conditioner compressor to engine and
tighten to the specified torque.
Torque :
M8 bolts : 22 N´m (2.2 Kg´m/16 lb ft)
M10 bolts : 43 N´m (4.4 Kg´m/32 lb ft)
10. Install power steering pump, tighten fixing bolt to the
specified torque.
Torque :
M8 bolts : 22N´m (2.2 Kg´m/16 lb ft)
M10 bolts : 46 N´m (4.7 Kg´m/34 lb ft)
11. Move drive belt tensioner to loose side using wrench,
then install drive belt to normal position.
850RW001
Legend
(1) Crankshaft Pulley
(2) Cooling Fan Pulley
(3) Tensioner
(4) Generator
(5) Air Conditioner Compressor
(6) Power Steering Oil Pump
(7) Drive Belt
12. Install upper fan shroud.
13. Reconnect radiator upper and lower hoses.
14. Reconnect coolant reserve tank hose to radiator.
15. Reconnect generator harness connector.
16. Reconnect starter harness connector.
17. Reconnect bonding cable terminal on left bank
18. Reconnect bonding cable terminal on the back of right
dash panel.19. Reconnect ground cable between engine and
chassis.
20. Reconnect harness connector to transmission and
install transmission harness bracket on engine left
side.
21. Reconnect three engine harness connectors.
22. Reconnect vacuum booster hose.
23. Reconnect canister vacuum hose.
24. Install air cleaner assembly.
25. Reconnect air duct.
26. Reconnect accelerator cable and automatic cruise
control cable to throttle valve on common chamber.
035RW007
Legend
(1) Throttle Valve Assembly
(2) Throttle Lever
(3) Idle Air Control Valve
(4) Throttle Position Sensor
27. Install engine hood to the original position.

Refer to installation procedure for Body section in
this manual.
Accelerator pedal cable adjustment
1. Loosen adjusting nut and lock nut.
2. Pull outer cable while fully closing 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.

6A±51
ENGINE MECHANICAL
If it does not reach the stopper screw, repeat from
step 1.
130RW004
Legend
(1) Clearance
(2) Lock Nut
(3) Adjusting Nut

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±54
ENGINE MECHANICAL
2. Tighten the M5 bolt to a suitable torque to prevent
the sub gear from moving .
014RW025
3. Install camshaft drive gear assembly and tighten
three bolts to the specified torque.
Torque: 10 N´m (1.0 Kg´m/89 lb in)
4. Install camshaft assembly and camshaft brackets,
tighten twenty bolts on one side bank to the specified
torque.
1. Apply engine oil to camshaft journal and bearing
surface of camshaft bracket.
2. Align timing mark on intake camshaft (one dot for
right bank, two dots for left bank) and exhaust
camshaft (one dot for right bank, two dots for left
bank) to timing mark on camshaft drive gear (one
dot).
014RW020
Legend
(1) Intake Camshaft Timing Gear for Right Bank
(2) Intake Camshaft Timing Gear for Left Bank
(3) Exhaust Camshaft Timing Gear
(4) Discrimination Mark
LI: Left Bank Intake
RI: Right Bank Intake
LE: Left Bank Exhaust
RE: Right Bank Exhaust
014RW023
Legend
(1) Right Bank Camshaft Drive Gear
(2) Left Bank Camshaft Drive Gear
(3) Timing Mark on Drive Gear
(4) Dowel Pin