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17. Disconnect the oxygen (O2) sensor connector, if
equipped.
18. Disconnect the fuel injector harness connectors.
19. Disconnect the MAT, MAP sensor connectors.
20. Disconnect the throttle position sensor (TPS) con-
nector.
21. Disconnect the generator voltage regulator connec-
tor and power lead.
22. Remove the electrical harness clamp bolt.
23. Disconnect all of the necessary vacuum lines, in-
cluding the brake booster vacuum hose.
24. Disconnect the fuel feed line at the fuel rail.
25. Disconnect the throttle cable from the throttle body
and the intake manifold bracket.
26. Disconnect the surge tank coolant hose at the
throttle body.
27. Disconnect the heater outlet hose at the coolant
pipe.
28. Disconnect the heater inlet hose from the cylinder
head.
29. Disconnect the surge tank coolant hose from the
coolant pipe.
30. Disconnect the lower radiator hose from the coolant
pipe. Disconnect the starter solenoid ”S” terminal
wire. Remove the A/C compressor, if equipped. Re-
fer to Section 7B, Manual Control Heating, Ventila-
tion, and Air Conditioning Systems.
31. Remove the catalytic converter retaining nuts from
the exhaust pipe.
32. Remove the exhaust pipe.
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39. Connect the lower radiator hose to the coolant pipe.
40. Connect the upper radiator hose to the thermostat
housing.
41. Connect the surge tank coolant hose to the radia-
tor.
42. Connect the heater inlet hose to the cylinder head.
43. Connect the heater outlet hose to the coolant pipe.
44. Connect the coolant surge tank hose to the coolant
pipe.
45. Connect the surge tank coolant hose to the throttle
body.
46. Connect the throttle cable to the throttle body and
the intake manifold bracket.
47. Install the fuel pump fuse.
48. Connect the negative battery cable.
49. Refill the engine crankcase with engine oil.
50. Refill the engine coolant system. Refer to Section
1D, Engine Cooling.
51. Bleed the power steering system. Refer to Section
6A, Power Steering System.
52. Refill the A/C refrigerant system, if equipped. Refer
to Section 7B, Manual Control Heating, Ventilation,
and Air Conditioning System.
53. Install the hood. Refer to Section 9R, Body Front
End.
PISTONS AND RODS
Tools Required
KM–427 Piston Pin Service Set
KM 470–B Angular Torque Gauge
Removal Procedure
1. Remove the cylinder head with the intake manifold
and the exhaust manifold attached. Refer to ”Cylin-
der Head and Gasket” in this section.
2. Remove the oil pan. Refer to ”Oil Pan” in this sec-
tion.
3. Remove the oil suction pipe bolts.
4. Remove the oil suction pipe.
5. Move the piston to the bottom of the piston stroke.
6. Mark the connecting rod cap for position.
7. Remove the connecting rod cap bolts.
8. Remove the connecting rod cap and the lower con-
necting rod bearing.
9. Remove the upper piston connecting rod bearing.
10. Ridge ream the cylinder wall.
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21. Install the oil suction pipe.
22. Install the oil suction pipe bolts.
Tighten
Tighten the oil suction pipe bolts to 10 NSm (89 lb–in).
23. Install the oil pan. Refer to ”Oil Pan” in this section.
24. Install the cylinder head with the intake manifold
and the exhaust manifold attached. Refer to ”Cylin-
der Head and Gasket” in this section.
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UNIT REPAIR
CYLINDER HEAD AND VALVE TRAIN
COMPONENTS
Tools Required
MKM–571–B Gauge
KM–340–0 Cutter Set
KM–340–7 Guide Drift
KM–340–13 Cutters
KM–340–26 Cutters
KM–348 Valve Spring Compressor
KM–653 Adapter
KM–805 Valve Guide Reamer
Disassembly Procedure
1. Remove the cylinder head with the intake manifold
and the exhaust manifold attached. Refer to ”Cylin-
der Head and Gasket” in this section.
2. Remove the engine coolant temperature sensor.
3. Remove the exhaust manifold heat shield bolts.
4. Remove the exhaust manifold heat shield.
5. Remove the exhaust manifold retaining nuts in the
sequence shown.
6. Remove the exhaust manifold.
7. Remove the exhaust manifold gasket.
8. Remove the exhaust manifold studs.
9. Remove the thermostat housing mounting bolts.
10. Remove the thermostat housing assembly.
11. Remove the fuel rail retaining bolts and the fuel rail
assembly.
12. Remove the intake manifold retaining nuts and re-
taining bolts in the sequence shown.
13. Remove the intake manifold.
14. Remove the intake manifold studs.
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35. Remove the valves. Maintain the original position of
the valves for installation.
36. Remove the valve stem seals.
Cylinder Head Inspection
1. Clean the sealing surfaces.
2. Inspect the cylinder head gasket and mating sur-
faces for leaks, corrosion, and blowby.
3. Inspect the cylinder head for cracks.
4. Inspect the length and the width of the cylinder
head using a feeler gauge and a straight edge.
5. Check the sealing surfaces for deformation and
warpage. The cylinder head sealing surfaces must
be flat within 0.050 mm (0.002 inch) maximum.
6. Measure the height of the cylinder head from seal-
ing surface to sealing surface. The cylinder head
height should be 134.08 to 134.23 mm. If the cylin-
der head height is less than 134.08 mm, replace
the cylinder head.
7. Inspect all threaded holes for damage.
8. Inspect valve seats for excessive wear and burned
spots.
Valve Inspection
1. Inspect the valve stem tip for wear.
2. Inspect the valve key grooves and the oil seal
grooves for chips and wear.
3. Inspect the valves for burns or cracks.
4. Inspect the valve stem for burrs and scratches.
5. Inspect the valve stem. The valve stem must be
straight.
6. Inspect the valve face for grooving. If the groove is
so deep that refacing the valve would result in a
sharp edge, replace the valve.
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7. Inspect the valve spring. If the valve spring ends
are not parallel, replace the valve spring.
8. Measure the valve spring height. Refer to ”Engine
Specifications” in this section. If the valve spring
height does not match the specifications, replace
the valve spring.
9. Inspect the valve spring seating surface of the
valve rotators for wear or gouges. Replace as re-
quired.
Cleaning Procedure
1. Clean the cylinder head.
2. Clean the valve guides.
3. Clean all of the threaded holes.
4. Clean the valves of carbon, oil, and varnish.
Cylinder Head Overhaul
Valve Grind–in
1. Lubricate the valve stem using a fine–grained
paste.
2. Lift the valve rhythmically from the seat with a com-
mercially available valve grinding tool in order to
distribute the paste.
3. Check the contact pattern on the valve head and in
the cylinder head.
4. Clean the valves, the valve guides, and the cylinder
head.
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Valve Grind
1. Ensure that there are no crater line burns on the
valve cone.
2. The valve may be reground only two times. Do not
grind the valve stem end.
3. The angle at the valve face is 45 degrees.
4. Inspect the assembly height of the intake valves
and the exhaust valves.
Valve Guide – Ream
1. Measure the diameter of the valve guide using the
gauge MKM–571–B and a commercially available
inside micrometer.
Important : Valve oversizes may already have been fitted
in production.
2. An oversize service code is on the valve guide and
the valve stem end. The following table gives the
correct size, reamer, and production code for each
service.
Size
ReamerProduction
CodeService
Code
Normal––K
0.075KM–8051K1
0.150–2K2
3. Ream the valve guide from the upper side of the
cylinder head to the next oversize.
4. After reaming, cross out the code and emboss the
valve guide with the new code.
Valve Seat – Cut
1. Place the cylinder head on wooden blocks.
2. Cut the intake and the exhaust valve seats using
the guide drift KM–340–7 as follows:
S Valve seat – A 45–degree surface using the cut-
ter KM–340–13.
S Upper correction angle – A 30–degree surface
using the cutter KM–340–13.
S Lower correction angle – A 60–degree surface
using the cutter KM–340–26.
3. Clean the chippings from the cylinder head.
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4. Inspect the dimension for the valve seat width.
S Intake: 1.17 to 1.57 mm (0.046 to 0.062 inch).
S Exhaust: 1.4 to 1.8 mm (0.055 to 0.071 inch).
5. Inspect the assembly height of the intake valves
and the exhaust valves. If the dimension is exceed-
ed, install new valves. Inspect the assembly height
of the intake valves and the exhaust valves again. If
the valve assembly height is still too large despite
replacing the valves, replace the cylinder head.
Assembly Procedure
1. Install the valve stem seals.
2. Lubricate the valve stems with engine oil.
3. Carefully install the valves in their original positions.
Do not damage the valve stem seals.
4. Install the valve springs in their original positions.
5. Install the valve spring caps.
6. Compress the valve springs with the valve spring
compressor KM–348 and adapter KM–653.
7. Install the valve keys.
8. Remove the valve spring compressor KM–348 and
adapter KM–653.
9. Lubricate the valve tappet adjusters with engine oil.
10. Install the valve tappet adjusters.