Page 1441 of 6020

ENGINE MECHANICAL (4JK1/4JJ1) 6A-81
54. Remove the cylinder head assembly.
• Loosen the cylinder head bolts in the order
described in the drawing.
• Remove the cylinder head gasket.
Note:
Replace the head gasket with a new one once it is
removed.
RTW 56ASH008601
Disassembly
1. Remove the throttle assembly.
• Refer to procedure for Intake Manifold in this
manual.
2. Remove the intake manifold assembly. • Refer to procedure for Intake Manifold in this
manual.
3. Remove the turbocharger. • Refer to “Turbocharger and Exhaust Manifold”.
4. Remove the exhaust manifold assembly. • Refer to procedure for Turbocharger and
Exhaust Manifold in this manual.
5. Remove the water outlet pipe.
6. Remove the valve stem cap.
Refer to procedure for valve stem and valve in this manual.
7. Remove the split collar. • Use a replacer to compress the valve spring to
remove the split collar.
Special tool
Valve spring replacer: 5-8840-2818-0 (1)
Pivot assembly: 5-8840-2819-0 (2)
RTW 56ASH012301
8. Remove the spring upper seat.
• Remove the special tool to remove the uppe
r
seat.
9. Remove the valve spring. • Put the removed valve springs in order b
y
cylinder number.
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ISUZU KB P190 2007
Page 1442 of 6020
6A-82 ENGINE MECHANICAL (4JK1/4JJ1)
10. Remove the intake and exhaust valve.
• Sort the removed valves according to cylinders
by using tags others.
LNW 21BSH016801
11. Remove the valve stem oil seal.
• Refer to procedure for valve stem and valve in
this manual.
12. Remove the spring lower seat.
13. Remove the valve guide. • Use the valve guide replacer to press out the
valve guides from the bottom side of the
cylinder head.
Special tool
Valve guide remover and installer:
5-8840-2816-0
RTW 56ASH008701
14. Remove the cam end gasket (1).
RTW 56ASH020501
15. Remove the oil seal.
RTW 56ASH008801
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Page 1443 of 6020

ENGINE MECHANICAL (4JK1/4JJ1) 6A-83
Inspection
Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is
discovered during inspection.
Cylinder Head Lower Face Warpage
1. Use a straight edge and a thickness gauge to
measure the four sides and the two diagonals o
f
the cylinder head lower face.
2. The cylinder head lower surface warpage is more than the limit, it should be replaced.
RTW 56ASH008901
Cylinder Head Lower Face W arpage mm (in)
Standard 0.05 (0.002) or less
Limit 0.20 (0.0079)
NOTE:
The cylinder head lower face cannot be regrind.
011RY00013
Cylinder Head Height (H) (Reference) mm (in)
Standard 143.4 (5.646)
RTW 56ASH017401
Manifold Fitting Face Warpage
Use a straight edge and a feeler gauge to measure the
manifold cylinder head fitting face warpage.
Regrind the manifold cylinder head fitting surfaces if the
measured values are greater than the specified limit but
less than the maximum grinding allowance.
If the measured values exceed the maximum grinding
allowance, the cylinder head must be replaced.
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Page 1444 of 6020

6A-84 ENGINE MECHANICAL (4JK1/4JJ1)
Manifold Fitting Face W arpage mm (in)
Standard 0.05 (0.002) or less
Limit 0.20 (0.008)
Maximum Grinding Allowance 0.40 (0.016)
RTW 56ASH017501
Exhaust Manifold Warpage
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.
Exhasut Manifold W arpage mm (in)
Standard 0.05 (0.002) or less
Limit 0.20 (0.008)
027RY00002
Valve Stem Cap
Make the necessary part replacements.
If excessive wear or damage is discovered during
inspection.
Valve Stem Outside Diameter
Measure the valve stem diameter at three points.
If the measured value is less than the specified limit, the
valve and the valve guide must be replaced as a set.
Valve Stem Outside Diameter mm (in)
Intake Valve Exhaust Valve
Standard 6.955 – 6.970
(0.2738 – 0.2744) 6.939 – 6.949
(0.2732 – 0.2736)
Limit 6.935
(0.2730) 6.920
(0.2724)
011LX027
Valve Stem and Valve Guide Clearance
1. Measure the valve stem outside diameter.
Refer to the item “Valve Stem Outside Diameter”.
2. Use a caliper calibrator or a telescoping gauge to measure the valve guide inside diameter.
If the measured values exceed the specified limit, the valve and the valve guide must be replaced as
a set.
Valve Stem Clearance mm (in)
Intake Valve Exhaust Valve
Standard0.039 – 0.071
(0.0015 – 0.0028) 0.064 – 0.096
(0.0025 – 0.0038)
Limit 0.200
(0.008) 0.250
(0.0098)
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Page 1445 of 6020

ENGINE MECHANICAL (4JK1/4JJ1) 6A-85
011RY00023
Valve Thickness
Measure the valve thickness.
If the measured value is less than the specified limit, the
valve and the valve guide must be replaced as a set.
Intake and Exhasut Valve Thickness mm (in)
Standard 1.32 (0.052)
Limit 1.1 (0.043)
014RY00020
Valve Depression
1. Install the valve (1) to the cylinder head (2).
2. Use a depth gauge or a straight edge with steel rule to measure the valve depression from the
cylinder head lower surface.
If the measured value exceeds the specified limit, the valve seat insert must be replaced.
Valve Depression mm (in)
Standard 1.8 (0.07)
Limit 2.5 (0.098)
014RY00021
Valve Contact Width
1. Check the valve contact faces for roughness and
unevenness. Make smooth the valve contact
surfaces.
2. Measure the valve contact width.
If the measured value exceeds the specified limit, the valve seat insert must be replaced.
Valve Contact W idth
mm (in)
Intake Exhaust
Standard 1.7 (0.067) 2.0 (0.079)
Limit 2.2 (0.087) 2.5 (0.098)
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Page 1446 of 6020
6A-86 ENGINE MECHANICAL (4JK1/4JJ1)
014RY00027
Repair of the seat surface
• Remove carbon from the surface of the valve
insert seat.
• Use a seat cutter to minimize the scratch and
other roughness (15/45/75 degree-blade), thereb
y
returning the contact width to the standard value.
LNW 21BSH018201
Note:
Remove only scratches and roughness, and do not cut
the surface too much.
Use the free adjustment valve cutter pilot.
Do not let the valve cutter pilot waver inside the valve
guide.
Valve Seat Angle Degree
45
LNW 21BSH056101
• Attach compound in the valve insert seat.
• Insert the valve into the valve guide.
•
Attach compound on the valve seat surface, rotate
the valve and hit it lightly to grind it, and confirm
that it has even contact all round.
Note:
Remove compound completely after grinding.
LNW 21BSH031801
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Page 1447 of 6020

ENGINE MECHANICAL (4JK1/4JJ1) 6A-87
Remove the valve seat insert
• Arc-weld the entire inner diameter of the valve seat
insert.
• Cool the valve seat insert for two to three minutes.
Contraction due to cooling makes it easier to
remove the valve seat insert.
• Remove the valve seat insert, using a scre
w
driver . Be sure not to harm the cylinder head.
LNW 21BSH056001
Legend
1. Arc-W eld
2. Valve Seat Insert
3. Screw Driver
Install the valve seat insert
• Carefully place a washer (the outer diameter is
smaller than the valve seat insert) on the valve
seat insert.
• Use the press to apply pressure gradually on the
washer, thereby pushing the valve seat insert.
Note:
Do not apply too much pressure with the press. Attach
compound on the valve seat surface, rotate the valve
and hit it lightly to grind it, and confirm that it has even
contact all round.
LNW 21BSH018601
Legend
1. Attach Compound
2. Valve Seat
3. Press
Reassembly
1. Install the oil seal.
• Install on the surface of the injection pipe insert.
• Hammer it in so that the seal does not incline.
Note:
Be sure not to harm the lip.
Special tool
Injection pipe oil seal installer: 5-8840-2820-0
RTW 56ASH008801
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ISUZU KB P190 2007
Page 1448 of 6020

6A-88 ENGINE MECHANICAL (4JK1/4JJ1)
RTW 56ASH009101
Legend
1. Cylinder Head
2. Oil Seal Installer
2. Install the valve guide.
• Hammer in the valve guide from the uppe
r
surface of the cylinder head, using the valve
guide installer.
Special tool
Valve guide remover and installer:
5-8840-2816-0
Note:
W hen replacing the valve guide, it must be replaced
together with the valve.
RTW 56ASH009001
• Height from the upper surface of the cylinder
head to the edge surface of the valve guide
RTW 56ASH023001
Legend
1. 12.6 ± 0.1 mm (0.50 ± 0.0039 in)
2. Cylinder Head
3. Install the valve spring lower seat.
4. Install the valve stem oil seal. • Refer to procedure for valve stem and valve in
this manual.
5. Install the intake and exhaust valve. • Apply engine oil on the valve stem part and
install the valve.
6. Install the valve spring, the valve spring upper seat and the split collar.
• Refer to procedure for valve stem and valve in
this manual.
7. Install the rocker arm and shaft assembly. • Refer to procedure for valve stem and valve in
this manual.
8. Install the exhaust manifold assembly. • Refer to procedure for Turbocharger and
Exhaust Manifold in this manual.
9. Install the turbocharger. • Refer to procedure for Turbocharger and
Exhaust Manifold in this manual.
10. Install the intake manifold assembly. • Refer to procedure for Intake Manifold in this
manual.
11. Install the throttle assembly. • Refer to procedure for Intake Manifold in this
manual.
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ISUZU KB P190 2007