engine ISUZU TROOPER 1998 Service Repair Manual

6A±63
ENGINE MECHANICAL
Camshaft
Camshaft and Associated Parts
014RW040
Legend
(1) Camshaft Bracket Fixing Bolt
(2) Camshaft Bracket
(3) Camshaft Assembly Intake
(4) Camshaft Assembly Exhaust
(5) Pulley Fixing Bolt(6) Camshaft Drive Gear Pulley
(7) Retainer Fixing Bolt
(8) Retainer
(9) Camshaft Drive Gear
(10) Oil Seal
Disassembly
1. Remove fixing bolt (5) for camshaft drive gear pulley
using the 5±8840±2447±0 universal holder.

6A±64
ENGINE MECHANICAL
014RW060
2. Remove twenty fixing bolts from inlet and exhaust
camshaft bracket on one side bank, then camshaft
brackets (2).
014RW027
3. Remove camshaft assembly (3), (4).
4. Remove three fixing bolts (7) from camshaft drive
gear retainer (8), then camshaft drive gear assembly.
Inspection and Repair
1. Use a micrometer to measure the cam lobe height
and uneven wear. Replace the camshaft if either the
lobe height or the uneven wear exceeds the specified
limit.
Lobe height : 44.709 mm (1.7602 in)
Uneven wear : 0.05 mm (0.0020 in)
014RW043
2. Use a micrometer to measure the diameter and the
uneven wear of the camshaft journals.
Replace the camshaft if the diameter or the uneven
wear exceeds the specified limit.
Journal Diameter
Standard : 25.972 mm±25.993 mm
(1.0225 in±1.0233 in)
Limit : 25.8 mm (1.0157 in)
Uneven wear : 0.05 mm (0.0020 in)
014RS023
3. Place the camshaft on V±blocks.
Slowly rotate the camshaft and measure the runout
with a dial indicator.
Replace the camshaft if the runout exceeds the
specified limit.

6A±65
ENGINE MECHANICAL
Runout
Limit : 0.1 mm (0.0039 in)
014RW044
4. Measure the camshaft journal oil clearance.
1. Measure the camshaft bracket housing inside
diameter.
NOTE: Tighten camshaft bracket (2) to specified torque
before measuring the camshaft bracket inside diameter.
Torque : 10 N´m (1.0 Kg´m/89 lb in)
014RW031
2. Subtract the camshaft outside diameter from the
camshaft bracket housing inside diameter.
Oil Clearance
Standard : 0.027 mm±0.078 mm
(0.0011 in±0.0031 in)
Limit : 0.11 mm (0.0043 in)
014RW037
5. Replace the cylinder head and/or camshaft if the
measured oil clearance exceeds the specified limit.
1. Carefully clean the camshaft journal, the
camshaft bracket, and the cylinder head.
2. Install camshaft assembly and camshaft brackets
(2), tighten twenty bolts (1) on one side bank to
the specified torque.
Torque: 10 N´m (1.0 Kg´m/89 lb in)
014RW031
3. Measure the camshaft thrust clearance with a dial
indicator. Replace the camshaft and/or the
cylinder head if the camshaft thrust clearance
exceeds the specified limit.
Camshaft thrust Clearance
Standard : 0.03 mm±0.08 mm
(0.0012 in.±0.0031 in.)

6A±66
ENGINE MECHANICAL
Limit : 0.12 mm (0.0047 mm)
014RW035
Reassembly
1. Install camshaft drive gear assembly and tighten
three bolts to specified torque.
Torque: 10 N´m (1.0 Kg´m/89 lb in)
2. Tighten sub gear setting bolt.
1. Use 5±8840±2443±0 to turn sub gear to right
direction until the M5 bolt hole aligns between
camshaft driven gear and sub gear.
2. Tighten M5 bolt suitable torque for prevent
moving the sub gear.
014RW041
3. 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) Discerning Mark
LI: Left Bank Intake
RI: Right Bank Intake
LE: Left Bank Exhaust
RE: Right Bank Exhaust

6A±67
ENGINE MECHANICAL
014RW023
Legend
(1) Right Bank Camshaft Drive Gear
(2) Left Bank Camshaft Drive Gear
(3) Timing Mark on Drive Gear
(4) Dowel Pin
014RW024
Legend
(1) Right Bank
(2) Left Bank(3) Alignment Mark on Camshaft Drive Gear
(4) Alignment Mark on Camshaft
(5) Alignment Mark on Retainer
3. Tighten twenty bolts in numerical order on one
side bank as shown in the illustration.
Torque: 10 N´m (1.0 Kg´m/89 lb in)

6A±68
ENGINE MECHANICAL
014RW031
4. If the oil seal requires replacement, use the
5±8840±2445±0 to install the oil seal.
014RW034
5. Tighten bolt for camshaft drive gear pulley to the
specified torque using the 5±8840±2447±0 universal
holder.
Torque: 98 N´m (10.0 Kg´m/72 lb ft)
014RW060

6A±69
ENGINE MECHANICAL
Crankshaft
Crankshaft and Associated Parts
013RW009
Legend
(1) Cylinder Head Assembly
(2) Crankcase with Oil Pan
(3) Oil Pipe and O-Ring
(4) Oil Strainer and O-Ring
(5) Oil Pump Assembly
(6) Cylinder Block Side Bolts
(7) Oil Gallery(8) Piston and Connecting Rod Assembly
(9) Flywheel
(10) Rear Oil Seal Retainer and Oil Seal
(11) Main Bearing Cap
(12) Crankshaft
(13) Main Bearing Cap Fixing Bolts
(14) Oil Gallery Fixing Bolts
Disassembly
1. Remove cylinder head assembly (1). Refer to
ªCylinder Headº in this manual.
2. Remove crankcase with oil pan (2). Refer to ªOil Pan
and Crankcaseº in this manual.CAUTION: Take care not to damage or deform the
sealing flange surface of crankcase.
3. Remove oil pipe and O-ring (3).
4. Remove oil strainer and O-ring (4).
5. Remove oil pump assembly (5).
6. Remove crankcase side bolts (6).

6A±70
ENGINE MECHANICAL
7. Remove oil gallery (7).
8. Remove piston and connecting rod assembly (8).
Refer to ªPiston, Piston Ring and Connecting Rodº in
this manual.
9. Remove flywheel (9).
10. Remove rear oil seal retainer (10).
11. Remove main bearing cap (11).
12. Remove crankshaft (12).
Inspection and Repair
1. Crankshaft
Set the dial indicator as shown in the illustration and
measure the crankshaft thrust clearance. If the thrust
clearance exceeds the specified limit, replace the
thrust bearings as a set.
Thrust Clearance
Standard : 0.06 mm±0.24 mm
(0.0024 in±0.0094 in)
Limit : 0.30 mm (0.0118 in)
015RS003
Main Bearing Clearance
1. Remove the bearing caps and measure the oil
clearance.
2. Remove the main bearing cap fixing bolts in the
sequence shown in the illustration.
Arrange the removed main bearing caps in the
cylinder number order.
Remove the main bearings.
015RS004
3. Remove the crankshaft.
Remove the main bearings.
4. Clean the upper and lower bearings as well as the
crankshaft main journal.
5. Check the bearings for damage or excessive wear.
The bearings must be replaced as a set if damage or
excessive wear is discovered during inspection.
6. Set the upper bearings and the thrust washers to their
original positions.
Carefully install the crankshaft.
7. Set the lower bearings to the bearing cap original
position.
8. Apply plastigage to the crankshaft journal unit as
shown in the illustration.
NOTE: Do not set the plastigage on the oil hole.
015RS005
9. Install main bearing caps, oil gallery and crank case
bolts in the order shown, and tighten each bolt to the
specified torque.

6A±71
ENGINE MECHANICAL
NOTE: Do not apply engine oil to the crank case side
bolts.
Main bearing cap bolts.
Torque: 39 N´m (4.0 Kg´m/29 lb ft)
Oil gallery fixing bolts.
Torque:
1st step: 29 N´m (3.0 Kg´m/21 lb ft)
2nd step 55
~ 65

Crank case side bolts
Torque : 39 N´m (4.0 Kg´m/29 lb ft)
NOTE: Do not allow the crankshaft to rotate.
015RS006
10. Remove the main bearing caps in the sequence
shown in the illustration.
015RS004
11. Measure the plastigage width and determine the oil
clearance. If the oil clearance exceeds the specified
limit, replace the main bearings as a set and/or
replace the crankshaft.
Standard : 0.019 mm±0.043 mm
(0.0007 in±0.0017 in)Limit : 0.08 mm (0.0031 in)
015RS008
12. Clean the plastigage from the bearings and the
crankshaft.
Remove the crankshaft and the bearings.
Crankshaft (12) Inspection
Inspect the surface of the crankshaft journal and crank
pins for excessive wear and damage. Inspect the oil seal
fitting surfaces for excessive wear and damage. Inspect
the oil ports for obstructions.
Inspection and Repair
1. Carefully set the crankshaft on the V±blocks. Slowly
rotate the crankshaft and measure the runout. If the
crankshaft runout exceeds the specified limit, the
crankshaft must be replaced.
Runout : 0.04 mm (0.0016 in)
015RS007

6A±72
ENGINE MECHANICAL
2. Measure the diameter and the uneven wear of main
journal and crank pin. If the crankshaft wear exceeds
the specified limit, crankshaft must be replaced.
Main journal diameter : 63.918 mm±63.933 mm
(2.5165 in±2.5170 in)
Crank pin diameter : 53.922 mm±53.937 mm
(2.1229 in.±2.1235 in.)
Uneven wear limit : 0.005 mm (0.0002 in)
015RS009
Crankshaft Bearing Selection
When installing new crankshaft bearings or replacing
bearings, refer to the selection table below. Select and
install the new crankshaft bearings, paying close
attention to the cylinder block journal hole.
1. Diameter size mark (1) and the crankshaft journal.
015RS010
2. Diameter size mark (1).
The diameter size marks are stamped on the No.1
crankshaft balancer as shown in the illustration.
015RS011
NOTE: Take care to ensure the bearings are positioned
correctly.
015RS012
Legend
(1) Number 1 and 4 main bearing upper and lower
(2) Number 2 and 3 main bearing upper
(3) Number 2 and 3 main bearing lower