ISUZU TROOPER 1998 Service Repair Manual

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 19
3) Temporarily tighten the six injection pump nuts 5.
The injection pump nuts will be finally tightened after
the injection pump rear bracket bolts.
4) Install the injection pump rear bracket 6 and the rear
bracket bolts 7 to the cylinder body.
5) Install the rear bracket bolts 8 to the injection pump
bracket 9.
Do not tighten the bolts.
The rear bracket bolts 7 and 8 will be finally tightened
to the specified torque after the injection pump nuts.
6) Tighten the injection pump bracket bolts 7 to the
specified torque.
7) Tighten the injection pump bracket bolts 8 to the
specified torque.
9. Timing Gear Oil Pipe
1) Install the oil pipe to the timing gear case and idler
gear "A".
2) Tighten the oil pipe eye bolt 1 and bolt 2 to the
specified torque.
8. Timing Gear Case Cover
1) Align the gear case with the timing gear case knock
pin and then install the timing gear case cover.
2) Tighten the gear case cover bolts to the specified
torque.
7. Noise Cover Spacer
6. Lower Noise Shield Cover
5. Upper Noise Shield Cover
206(21/152)N·m(Kg·m/lb·ft)
206(21/152)N·m(Kg·m/lb·ft)
13 (1.3/9)N·m(Kg·m/lb·ft)

6A2 Ð 20 4JG2-NA/4JG2-TURBO ENGINE
4. Cranshaft Damper Pulley
Tighten the crankshaft damper pulley bolt to the specified
torque.
NOTE:
Hold the flywheel ring gear stationary to prevent the
crankshaft from turning when tightening the damper
pulley.
3. Cooling Fan Assembly
·Mount fan pulley, distance piece, and cooling fan
asm (in this order) on the water pump, and
tighten to the specified torque.
2. AC Generator Drive Belt
·Install AC Generator drive belt and adjust belt
tension.
·Refer to Drive Belt Adjustment in section 6B.
1. P/S Pump Drive Belt
·Install P.S pump drive belt and adjust belt tension.
·Refer to Drive Belt Adjustment in section 6B.
206(21/152)N·m(Kg·m/lb·ft)
206(21/152)N·m(Kg·m/lb·ft)

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 21
VALVE STEM OIL SEAL & VALVE SPRING
REMOVAL
Preparation
·Disconnect battery ground cable.
1. Air cleaner Cover & Air Duct (4JG2-T Only)
·Disconnect air hoses.
·Release clips and bands and remove air cleaner
cover.
2. Intercooler Assembly (4JG2-T Only)
·(Refer to intercooler removal steps in this section)
3. Oil Level Gauge Tube
4. Cylinder Head Cover
5. Rocker Arm Shaft Assembly
·Loosen bolts and nuts of rocker arm shaft
·Bracket by turns and removal rocker
·Shaft asm.
6. Valve Spring
·Apply compressed air to cylinder from the glow
plug hole hold the valve in place.
·Using special tool, compress valve spring and
removal split collar.
Valve spring compressor: 9-8523-1423-0 (J-29760)

6A2 Ð 22 4JG2-NA/4JG2-TURBO ENGINE
CAUTION
·Put removed valve springs in the order of cylinder
number.
7. Valve Stem Oil Seal
·Removal oil seal by pliers.
CAUTION
·Removed oil controller should not be reused.
CAUTION
·The painted area of the valve spring should be
facing toward.
·Apply compressed air to cylinder from the glow
plug hole to hold the valve in place.
·Install split collar by special tool.
Valve spring compressor: 9-8523-1423-0 (J-29760)
INSTALLATION
7. Valve Stem Oil Seal
·Install new oil seal to valve guide.
·Guide using special tool.
Special tool: 5-8840-2033-0
6. Valve Spring
·Attach the valve spring to the upper spring seat.
5. Rocker Arm Shaft Assembly
·Install rocker arm shaft with a larger oil hole (¿4)
to the front of engine.
·Align fixing bolt with not of rocker arm shaft and
tighten fixing bolt to the specified torque.
54 (5.5/40)
N·m(Kg·m/lb·ft)
4. Cylinder Head Cover
·Install cylinder head cover and tighten bolt to the
specified torque.
13 (1.3/113)
N·m(Kg·m/lb·in)

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 23
2. Intercooler Assembly (4JG2-T Only)
·Refer to intercooler installation steps in this
section.
1. Air Cleaner Cover & Air Duct (4JG2-T Only) 3. Oil Level Gauge Guide Tube
·Tighten guide tube to the specified torque.
19 (1.9/14)
N·m(Kg·m/lb·ft)

6A2 Ð 24 4JG2-NA/4JG2-TURBO ENGINE
ROCKER ARM SHAFT ASSEMBLY
REMOVAL
Preparation
·Disconnect battery ground cable.
1. Air Cleaner Cover & Air Duct (4JG2-T Only)
·Disconnect air hoses.
·Release clips and bands and remove air cleaner
cover.
2. Intercooler Assembly (4JG2-T Only)
·Refer to intercooler removal steps in this section.
3. Oil Level Gauge Tube
4. Cylinder Head Cover
5. Rocker Arm Shaft Assembly
·Loosen bolts and nuts of rocker arm shaft bracket
by turns and remove rocker shaft asm.

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 25
INSTALLATION
5. Rocker Arm Shaft Assembly
·Install rocker arm shaft with larger oil hole (¿4) to
the front of engine.
·Align fixing bolt with not of rocker arm shaft and
tighten fixing bolts to the specified torque.
54 (5.5/40)N·m (kg·m/lb·ft)
·Adjust valve clearance refreshing to section valve
clearance adjustment.
4. Cylinder Head Cover
·Install cylinder head cover and tighten bolts to the
specified torque.
3. Oil Level Gauge Guide Tube
·Tighten guide tube to the specified torque.
2. Intercooler Assembly (4JG2-T Only)
·Refer to intercooler installation steps in this
section.
1. Air Cleaner Cover & Air Duct (4JG2-T Only)
13 (1.3/113)N·m (kg·m/lb·in)
19 (1.9/14)N·m (kg·m/lb·ft)

6A2 Ð 26 4JG2-NA/4JG2-TURBO ENGINE
CYLINDER HEAD

4JG2-NA/4JG2-TURBO ENGINE 6A 2Ð 27
REMOVAL
Preparation
·Remove battery. (two batteries for cold area)
·Disconnect window washer hose, and remove
engine hood.
·Drain coolant.
·Space stand and front right tire.
1. Radiator Hose : Upper
·Disconnect upper radiator hose from engine side.
2. Air Cleaner Cover & Air Duct
3. Intercooler Assembly (4JG2-T Only)
·(Refer to intercooler removal steps in this section)
4. Oil Level Gauge Guide Tube
5. P/S Pump
·Loosen P/S pump fixing bolts and adjusting bolt
and remove two drive belts.
·Remove two fixing bolts (front side). A fixing nut
(rear side) and support P/S pump asm with oil
hoses by tying to body side.
6. A/C Compressor Assembly
·Remove A/C compressor fixing bolt (rear under
side of compressor) by using a long extension bar
at under side of wheel arch.
·Disconnect magnetic clutch harness connector.
·Remove fixing bolts (upper and front lower side of
compressor) and set A/C compressor asm with
pipe line on battery carrier.
7. Water Hose; CSD
·Disconnect CSD water hoses from heater hose
side.
8. Engine Harness
·Disconnect five harness connectors from units on
thermostat housing.
9. Heater Hose: Rear Side
·Disconnect heater hose from heater pipe.
10. Water Bypass Hose
·Disconnect water bypass hose from water pump.
11. Water Inlet Hose: Turbo (4JG2-T Only)
·Disconnect from water outlet pipe of engine.
12 Water Outlet Hose: Turbo (4JG2-T Only)
·Disconnect from water inlet pipe of engine.
13 Oil Feed Pipe: Turbo (4JG2-T Only)
·Remove two joint bolts (from turbocharger and
cylinder block) and oil feed pipe.
14. Oil Return Pipe Fixing Nut (4JG2-T Only)
·Remove oil return pipe fixing nut from cylinder
block.
15. Oil Cooler Hose

6A2 Ð 28 4JG2-NA/4JG2-TURBO ENGINE
16. Exh. Manifold; W/turbo (4JG2-T Only)
·Remove exh. manifold bracket fixing bolt from
exh. manifold.
·Remove exh. manifold fixing bolts and nuts from
cylinder head.
·After pulling out exh. manifold a little, remove oil
return pipe flange from stud bolt and remove exh.
manifold w/turbo.
17. Front Exhaust Pipe
18. Fuel Leak Off Hose
19. Cylinder Head Cover
20. Glow Plug Harness
21. Injection Pipe
·Loosen sleeve nuts on injection pump side.
·Disconnect sleeve nuts on injection pipe.
22. Fuel Leak Off Pipe
23. Rocker Arm Shaft Assembly
24. Push Rod
25. Cylinder Head W/inlet Manifold
·Disconnect cylinder head bolts in sequence shown
in Figure.
26. Cylinder Head Gasket
INSTALLATION
26. Cylinder Head Gasket
·Determine cylinder head gasket grade by
measuring projection of piston head.
·Install dowel in cylinder block.
·Install cylinder head gasket with top mark up.
25. Cylinder Head W/intake Manifold
·Clean up cylinder head lower surface and cylinder
body upper surface.
·Install cylinder head as softly.
·Apply engine oil to screw and seat of cylinder
head bolts.
·Tighten cylinder head bolts in following sequence.
24. Push Rod
·Inspect curvature, excessive wear and damage.
(Refer to push rod inspection)
1st Step
N·m (kg·m/lb·ft)
49 (5.0/36)
2nd Step
60°3rd Step
60°