engine ISUZU TROOPER 1998 Service Repair Manual

6A2 Ð 34 4JG2-NA/4JG2-TURBO ENGINE
OIL COOLER
REMOVAL
Preparation
·Disconnect battery ground cable
·Drain coolant
1. Air Cleaner Cover & Air Duct
2. Intercooler Assembly (4JG2-T Only)
·Refer to intercooler removal steps in this section
3. Front Exh. Pipe
·Disconnect front exhaust pipe from engine side
and intermediate pipe.
4. Heat Protector (4JG2-T Only)
5. Exh. Adapter (4JG2-T Only)
6. Oil Cooler
·Disconnect water inlet and outlet hose.
·Remove fixing bolts and oil cooler.
·Put rag to beneath side of oil cooler to prevent oil
leaking.

4JG2-NA/4JG2-TURBO ENGINE 6A2Ð 35
INSTALLATION
6. Oil Cooler
·Tighten oil cooler fixing bolt to the specified
torque and connect water hose.
5. Exh. Adapter (4JG2-T Only)
·Install exhaust duct with gasket and tighten fixing
bolts to the specified torque.
26 (2.7/20)N·m(Kg·m/lb·ft)
4. Heat Protector (4JG2-T Only)
3. Front Exh. Pipe
·Install front exhaust pipe and tighten fixing bolts
to the specified torque.
2. Intercooler Assembly (4JG2-T Only)
·Refer to intercooler installation steps in section.
·Pour coolant into radiator.
·Install battery ground cable.
·Start engine and check for oil and water leakage
carefully.
1. Air Cleaner Cover & Air Duct
67 (6.8/49)N·m(Kg·m/lb·ft)
Exh Dust Side
43 (4.4/32)N·m(Kg·m/lb·ft)
Intermediate pipe side 29 (3.0/22)N·m(Kg·m/lb·ft)

6A2 Ð 36 4JG2-NA/4JG2-TURBO ENGINE
OIL PUMP ASSEMBLY
REMOVAL
Preparation
·Disconnect battery ground cable.
·Lift up car.
·Drain engine oil.
NOTE
·Install drain plug with new washer.
1. Crankcase
·Refer to crankcase removal steps in this section
2. Oil Pump Assembly
·Remove oil pump asm from cylinder block.
INSTALLATION
·Prepare a solution of 80% engine oil and 20% molyb-
denum disulfide.
·Apply and ample coat of the solution to the teeth of
the oil pump pinion.
2. Oil Pump Assembly
·Apply engine oil to oil pipe o-ring and insert the
o-ring in o-ring hold on cylinder block.
·Install oil pump asm with oil pipe in cylinder block
and tighten fixing bolts to the specified torque.
19 (1.9/14)N·m(Kg·m/lb·ft)
·Tighten sleeve nut to the specified torque.
25 (2.5/18)N·m(Kg·m/lb·ft)
1. Crankcase
·Refer to crankcase installation steps in this section

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.

6A2 Ð 38 4JG2-NA/4JG2-TURBO ENGINE
·After tightening the nuts, make sure that the
crankshaft rotates smoothly.
2. Crankcase
·Refer to ÒCrankcaseÓ in this section.
1. Cylinder Head
·Refer to ÒCylinder HeadÓ installation in this sec-
tion.
1st step 29 (3.0/22) 2nd step 45° – 60°N·m(Kg·m/lb·ft)

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 39
CRANKSHAFT AND MAIN BEARING

6A2 Ð 40 4JG2-NA/4JG2-TURBO ENGINE
REMOVAL
1. Engine Assembly
·Refer to ÒEngine AssemblyÓ removal in this
section.
2. Crankshaft Damper Pulley
3. Timing Gear Case Cover
4. Oil Level Gauge and Guide Tube
5. Idler Gear
ÒBÓ and Shaft
6. Idler Gear
7. Injection Pump
8. Camshaft Timing Gear
9. Crankcase
10. Gear Case
11. Flywheel
12. Rear Plate
13. Connecting Rod Caps
14. Crankshaft Main Bearing Caps
15. Crankshaft and Main Bearings
INSTALLATION
15. Crankshaft and Main Bearings
·Install main bearings in the cylinder body and
main bearing cap respectively.
·Apply new engine oil to upper and lower main
bearings.
·Make sure that main bearing are in correct
position.
·Install crankshaft with care.
·Apply engine oil to the thrust washer.
·Install thrust washer on No. 3 journal.
Oil grooves in thrust washer must face the
crankshaft.
14. Crankshaft Main Bearing Caps
·Apply engine oil to the thread and seating surface
of each bearing cap fixing bolt.
·Install bearing caps in the order of numbers,
starting with cylinder body front side.
·Tighten main bearing fixing bolts to the specified
torque.

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 41
19 (1.9/14)N·m(Kg·m/lb·ft)
·After tightening the bolts, make sure that the
crankshaft rotates smoothly.
167 (17.0/123)N·m(Kg·m/lb·ft)
13. Connecting Rod Caps
·The cap number must be same as connecting rod
number.
·Apply engine oil to the thread and sealing surface
of each nut.
·Tighten nuts to the specified torque.
·After tightening the nuts, make sure that the
crankshaft rotates smoothly.
12. Rear Plate
·Tighten bolts to the specified torque.
82 (80/61)N·m(Kg·m/lb·ft)
11. Flywheel
·Tighten bolts to the specified torque.
118 (12.0/87)N·m(Kg·m/lb·ft)
10. Gear Case
·Tighten fixing bolts to the specified torque.
19 (1.9/14)N·m(Kg·m/lb·ft)
9. Crankcase
·Remove oil from oil pan mounting surface, and
dry the surface.
·Apply a proper wide bead of sealant (TB1207C or
equivalent) to the crankcase mounting surface.
The bead must be continuous.
·Crankcase must be installed within 5 minutes
after sealant application.
·Tighten fixing bolts and nuts to the specified
torque.
Bolts
1st step 29 (3.0/22) 2nd step 45° – 60°N·m(Kg·m/lb·ft)

6A2 Ð 42 4JG2-NA/4JG2-TURBO ENGINE
8. Camshaft Timing Gear
1) Install the camshaft timing gear to the camshaft.
The timing gear mark ("Y - Y") must be facing out-
ward.
2) Tighten the timing gear to the specified torque.
Nuts
6. Idler Gear
1) Apply engine oil to the idler gear and the idler gear
shaft.
The idler gear shaft oil hole must be facing up.
2) Position the idler gear setting marks "X" and "Y" so
that they are facing the front of the engine.
3) Align the idler gear "X" setting mark with the crank-
shaft timing gear 1 "X - X" setting mark.
4) Align the idler gear "Y" setting mark with the cam-
shaft timing gear 2 "Y - Y" setting mark.
5) Install the thrust collar and bolts to the cylinder body
through the shaft.
The thrust collar oil hole must be facing up, and the
thrust collar chamfered must be outward.
6) Tighten the idler gear bolt to the specified torque.
64 (6.5/47)N·m(Kg·m/lb·ft)
19 (1.9/14)N·m(Kg·m/lb·ft)
5. Idler Gear "B" and Shaft
1) Apply engine oil to the idler gear and the idler gear
shaft.
2) Align the idler gear "B" 3 "Z" setting mark with the
idler gear "A" 4 "Z - Z" setting mark.
3) Tighten the idler gear bolt to the specified torque.
76 (7.7/56)N·m(Kg·m/lb·ft)
24 (2.4/18)N·m(Kg·m/lb·ft)

4JG2-NA/4JG2-TURBO ENGINE 6A2 Ð 43
7. Injection Pump
1) Install the O-ring 1 to the injection pump flange 2.
2) Install the injection pump to the timing gear case.
Align the idler gear "B" 3 "V - V" mark with the
injection pump timing gear 4 "V" mark.
3) Temporarily tighten the six injection pump nuts 5.
The injection pump nuts will be finally tightened after
the injection pump rear bracket bolts.
7) Tighten the injection pump bracket bolts 8 to the
specified torque.
4. 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.
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 tight-
ened to the specified torque after the injection pump
nuts.
13 (1.3/9)N·m(Kg·m/lb·ft)
6) Tighten the infection pump bracket bolts 7 to the
specified torque.
20 (2.0/15)N·m(Kg·m/lb·ft)
40 (4.1/30)N·m(Kg·m/lb·ft)