1998 ISUZU TROOPER height

6A Ð 44 ENGINE MECHANICAL
INSPECTION REPAIR
Make the necessary adjustments, repairs, and part replacements if excessive wear or damage is discovered
during inspection.
1. Remove the gasket and any other material adhering to
the upper surface of the cylinder block.
Be very careful not to allow any material to accidentally
drop into the cylinder block.
Be very careful not to scratch the cylinder block.
2. Carefully remove the oil pump, Rear Oil Seal retainer,
and oil pan installation surface seal.
3. Wipe the cylinder block clean.
Cylinder Liner Projection Inspection
1. Hold a straight edge 1 along the top edge of the cylinder
liner to be measured.
2. Use a feeler gauge 2 to measure each cylinder liner
projection.
The difference in the cylinder liner projection height
between any two adjacent cylinders must not exceed
0.03 mm (0.0012 in).
0.0 – 0.1 (0.0000 – 0.0039)
mm(in.) Standard
Flatness
1. Remove the cylinder body dowel.
2. Set the cylinder liner remover to the cylinder liner.
3. Check that the remover shaft ankle is firmly gripping the
cylinder liner bottom edge.
4. Slowly turn the remover shaft handle counterclockwise
to pull the cylinder liner free.
Cylinder Liner Remover Ankle: 5-8840-2304-0
Cylinder Liner Remover: 9-8523-1169-0
NOTE:
Take care not to damage the cylinder body upper during the
cylinder liner removal procedure.
5. Use a straight edge 1 and a feeler gauge 2 to measure the
four sides and the two diagonals of the cylinder body
upper face.
If the measured values exceed the limit, the cylinder
body must be replaced.
0.20 (0.0079)
mm(in.) Limit

6A – 6 ENGINE MECHANICAL
SERVICE STANDARD
Enginemm (in)
Parts Items Service standard Service limit Remarks
Cylinder Head
Valve Spring
Valve and
Valve guide
Camshaft0.075 (0.0030) or less
95.0 (3.740)
45.7 (1.8)
—
241 (54.2)
6.959 – 6.977
(0.27 –0.272)
6.692 –6.970
(0.271 –0.272)
0.023 –0.056
(0.0009 – 0.0022)
0.03 – 0.063
(0.0011 – 0.0024)
8.0 (0.312)
1.1 (0.0433)
1.2 (0.0472)
1.2 (0.0472)
45°
2.1 (0.0827)
2.1 (0.0827)
0.08 (0.00314)
46.67 (1.8374)
46.77 (1.8413)
29.939 – 29.960
(1.167 – 1.168)
0.02 (0.0008) or less
0.40 – 0.082
(0.0016 – 0.0032)0.50 (0.0197)
—
44.8 (1.765)
1.6 (0.063)
210 (47.22)
6.92 (0.270)
6.90 (0.269)
0.19 (0.0074)
0.20 (0.0079)
—
1.6 (0.0630)
1.1 (0.0433)
1.1 (0.0433)
—
2.6 (0.1024)
2.6 (0.1024)
2.0 (0.00797)
46.57 (1.8335)
46.67 (1.8374)
29.84 (1.1748)
0.10 (0.0039)
0.12 (0.0047)Cannot be
reground Cylinder head lower surface for flatness
Cylinder head height
Free height
Squareness
Spring tension (when assembled) N(lb)
Diameter of Valve stem IN
EX
Valve and valve guide clearance IN
EX
Valve guide upper end height
(Measured from the Cylinder head upper
face)
Valve guide margin
Valve thickness IN
EX
Valve seat contact surface angle
Valve seat contact width IN
EX
End play
Cam lobe height IN
EX
Journal diameter
Runout
Camshaft oil clearance

6A – 42 ENGINE MECHANICAL
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.
4. Cylinder head lower surface for flatness.
Use a straight edge and a feeler gauge to measure
the cylinder head lower surface warpage.
If the measured values exceed the specified limit,
the cylinder head must be replaced.
Cylinder Head Lower Face Warpage:
Standard: 0.075 mm (0.0029 in) or less
Limit: 0.2 mm (0.0079 in)
Cylinder Head Height:
Standard: 95 mm (3.740 in)
5. Water jacket sealing plugs seating surfaces.
6. Use a straight edge and a feeler gauge to measure
the manifold cylinder head fitting face warpage.
If the measured values exceed the specified limit,
the manifold must be replaced.
Exhaust Manifold Warpage:
Standard: 0.05 mm (0.0020 in) or less
Limit: 0.20 mm (0.0079 in)
CAUTION: Do not attempt to weld the cylinder
head. Replace it.
REASSEMBLY
1. Cylinder Head
•Refer to “Cylinder Head Gasket”.
2. Glow Plug and Glow Plug Connector
•Tighten glow plugs.
Torque: 15 N·m (1.5 kg·m/11 lb ft)
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ENGINE MECHANICAL 6A – 49
INSPECTION AND REPAIR
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is
discovered during inspection.
1. Camshaft Journal diameter
1) Use a micrometer to measure each camshaft
journal diameter in two directions (1) and (2). If
the measured value is less than the specified
limit, the camshaft must be replaced.
Standard: 29.939 – 29.96 mm (1.1787 – 1.1795 in)
Limit: 29.84 mm (1.17 in)
2. Cam Height
1) Measure the cam height (H) with a micrometer.
If the measured value is less than the specified
limit, the camshaft must be replaced.
Standard: IN 46.62 mm (1.8354 in)
EX 46.72 mm (1.8394 in)
Limit: IN 46.57 mm (1.8335 in)
EX 46.67 mm (1.8374 in)3. Cam Run-Out
1) Mount the camshaft on V-blocks.
2) Measure the cam height (H) with a micrometer.
If the measured value is less than the specified
limit, the camshaft must be replaced.
Standard: 0.02 mm (0.0008 in) or less
Limit: 0.10 mm (0.0039 in)
4. Camshaft oil clearance
1) Clean the camshaft, camshaft bracket and
camshaft carrier.
2) Put camshaft carrier on the cylinder head.
3) Put camshaft on the camshaft carrier.
4) Put plastigauge on the camshaft journal.
5) Install camshaft bracket to original position and
tighten bolts to specified torque in the numerical
order shown in the illustration.
Torque: A; 22 N·m (2.2 kg·m/15.9 lb ft)
B; 38 N·m (3.9 kg·m/28.2 lb ft)
C; 22 N·m (2.2 kg·m/15.9 lb ft)
D; 38 N·m (3.9 kg·m/28.2 lb ft)
(1)Ft Rr
(2)
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H
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CC
D
B
CC
B
CC
D
CC
B
C
A AA A A A
AAAA
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ENGINE MECHANICAL 6A – 61
24. Remove fuel pipe between fuel pump and intake
manifold.
25. Remove fuel return pipe from rear of cylinder head.
26. Remove intake manifold assembly.
27. Disconnect glow plug harness and remove glow
plug.
28. Remove cylinder head cover.
29. Remove injector harness connector.
30. Disconnect harness connector from oil pressure
sensor and oil temperature sensor on the oil rail.
31. Remove injector harness assembly.
32. Remove injector clamp.
33. Remove injector is fixed bolts.
34. Remove injector assembly.
35. Remove oil rail.
36. Remove camshaft carrier assembly with camshaft.
37. Remove cylinder head assembly.
38. Disassemble valve spring according to the following
method.
1) Use valve spring compressor then remove split
collars.
2) Valve spring compressor: 5-8840-2441-0
NOTE: Put removed valve spring in order of cylinder
number.
39. Valve stem seal.
1) Use a screwdriver or pliers to remove valve
stem seal.
NOTE: Do not reuse removed valve stem seal.
INSPECTION AND REPAIR
Make the necessary adjustments, repairs and part
replacements if excessive wear or damage is
discovered during inspection.
Valve spring
CAUTION: Visually inspect the valve springs and
replace them if damage or abnormal wear is
evident.
1. Free height
1) Measure the free height of the springs. The
springs must be replaced if the height is below
the specified limit.
Standard: 45.85 mm (1.8051in)
Limit: 43.9 mm (1.7283 in)
2. Squareness
1) Measure the valve spring squareness with a
steel square.
2) Replace the valve springs if the measured value
exceeds the specified limit.
Limit: 1.6 mm (0.063 in)
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6A – 62 ENGINE MECHANICAL
3. Spring tension
1) Use a spring tester to compress the springs to
the installed height. Measure the compressed
spring tension.
2) Replace the springs if the measured tension is
below the specified limit.
Standard: 236.0 N (24 kg/53 lb)
Limit: 205.0 N (21 kg/46 lb)Valve Guide
CAUTION: Taking care not to damage the valve seat
contact surface, when removing carbon adhering to
the valve head.
Carefully inspect the valve stem for scratching or
abnormal wear. If these conditions are present, the
valve and the valve guide must be replaced as a set.
1. Valve Guide Clearance
1) Measure the valve stem diameter with a
micrometer.
If the valve stem diameter is less than the
specified limit, the valve and the valve guide
must be replaced as a set.
Diameter of Valve stem:Inlet
Standard: 6.959 – 6.977 mm (0.2740 – 0.2747 in)
Limit: 6.92 mm (0.2724 in)
Diameter of Valve stem:Exhaust
Standard: 6.952 – 6.97 mm (0.2737 – 0.2744 in)
Limit: 6.90 mm (0.2717 in)
2) Measure the inside diameter of the valve guide
with a micrometer.
3) Subtract the measured outer diameter of the
valve stem from the measured inner diameter of
the valve guide.
If the valve exceeds the specified limit, the valve
and the valve guide must be replaced as a set.
Inlet clearance
Standard: 0.023 – 0.053 mm (0.0009 – 0.0021 in)
Limit: 0.19 mm (0.0075 in)
Exhaust clearance
Standard: 0.03 – 0.063 mm (0.0012 – 0.0025 in)
Limit: 0.20 mm (0.0079 in)
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ENGINE MECHANICAL 6A – 63
Valve Guide Replacement
1. Using the special tool, drive out the valve guide
from the combustion chamber side.
Valve guide replacer: 9-8523-1212-0
2. Apply engine oil to the outside of the valve guide.
Using the special tool, drive in a new valve guide
from cylinder head upper face side, and check the
valve guide height.
Valve guide replacer: 9-8523-1212-0
Height: 8.0 mm (0.315 in)
NOTE: If the valve guide has been removed, both the
valve and the valve guide must be replaced as a set.
Valve Thickness
1. Measure the valve thickness.
2. If the measured value is less than the specified
limit, the valve and the valve guide must be
replaced as a set.
Inlet
Standard: 1.2 mm (0.0472 in)
Limit: 1.1 mm (0.0433 in)
Exhaust
Standard: 1.2 mm (0.0472 in)
Limit: 1.1 mm (0.0433 in)
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.
Standard: 68°
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6A – 64 ENGINE MECHANICAL
Valve Depression
1. Measure the valve stem height from the upper
surface of the cylinder head as shown in the
illustration.
Standard:
Intake side 35.59 mm (1.4012 in)
Exhaust side 35.49 mm (1.3972 in)
Limit:
Intake side 35.74 mm (1.4071 in)
Exhaust side 35.64 mm (1.4031 in)
Legend
(1) Intake Side
(2) Exhaust Side
Valve Contact Width
1. Check the valve contact faces for roughness and
unevenness. Make the valve contact surfaces
smooth.
2. Measure the valve contact width.
If the measured value exceeds the specified limit,
the valve seat insert must be replaced.
Inlet
Standard: 2.1 mm (0.0827 in)
Limit: 2.6 mm (0.1024 in)
Exhaust
Standard: 2.0 mm (0.0787 in)
Limit: 2.5 mm (0.0984 in)
Valve Seat Insert Replacement
Valve Seat Insert Removal
1. Arc weld the entire inside circumference of the
valve seat insert.
2. Allow the valve seat insert to cool for a few minutes.
This will invite contraction and make removal of the
valve seat insert easier.
3. Use a screwdriver to pry the valve seat insert free.
Take care not to damage the cylinder head.
4. Carefully remove carbon and other foreign material
from the cylinder head insert bore.

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