Nissan Frontier D22. Manual — part 682
CYLINDER HEAD
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2.
Use a reliable straightedge and feeler gauge to check the flat-
ness of cylinder head surface. Check the cylinder head sealing
surface flatness along the six positions as shown.
If it exceeds the limit, replace or resurface the cylinder head.
3.
Resurface the cylinder head as necessary to specification.
The limit of cylinder head resurfacing is determined by the cylinder block resurfacing:
Amount of cylinder head resurfacing is “A”.
Amount of cylinder block resurfacing is “B”.
4.
After resurfacing, the cylinder head,
●
Check that the camshaft rotates freely by hand. If resistance is felt, the cylinder head must be replaced.
CAMSHAFT VISUAL CHECK
Check the camshaft for scratches, seizure, and wear.
CAMSHAFT RUNOUT
1.
Measure the camshaft runout at the center of the journal.
2.
If the camshaft runout exceeds the limit, replace the camshaft.
CAMSHAFT CAM HEIGHT
1.
Measure camshaft cam height.
2.
If wear is beyond the limit, replace camshaft.
Cylinder head surface flatness
Limit
: 0.1 mm (0.004 in)
SEM294D
Maximum limit
: A + B = 0.2 mm (0.008 in)
Nominal cylinder head height
: 126.3 - 126.5 mm (4.972 - 4.980 in)
Runout (total indicator reading)
Standard
: less than 0.02 mm (0.0008 in)
Limit
: 0.04 mm (0.0016 in)
SEM926C
Standard cam height
Intake
: 41.755 - 41.945 mm
(1.644 - 1.651 in)
Exhaust
: 41.815 - 42.005 mm
(1.646 - 1.654 in)
Cam height wear limit
Intake & Exhaust
: 0.2 mm (0.008 in)
SEM549A
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CYLINDER HEAD
CAMSHAFT JOURNAL CLEARANCE
1.
Install camshaft bracket and tighten bolts to the specified torque.
2.
Measure inner diameter of camshaft bearing.
3.
Measure outer diameter of camshaft journal.
4.
If clearance exceeds the limit, replace camshaft and/or cylinder head.
CAMSHAFT END PLAY
1.
Install camshaft in cylinder head.
2.
Measure camshaft end play.
3.
If end play exceeds the limit, replace camshaft and remeasure
camshaft end play.
4.
If end play still exceeds the limit after replacing camshaft,
replace the cylinder head.
CAMSHAFT SPROCKET RUNOUT
1.
Install sprocket on camshaft.
2.
Measure camshaft sprocket runout.
3.
If it exceeds the limit, replace camshaft sprocket.
Standard inner diameter
No. 1 to No. 5 journals
: 28.000 - 28.025 mm
(1.1024 - 1.1033 in)
SEM295D
Standard outer diameter
No. 1 to No. 5 journals
: 27.935 - 27.955 mm
(1.0998 - 1.1006 in)
SEM012A
Camshaft journal clearance
Standard
: 0.045 - 0.090 mm (0.0018 - 0.0035 in)
Limit
: 0.12 mm (0.0047 in)
Camshaft end play
Standard
: 0.070 - 0.148 mm (0.0028 - 0.0058 in)
Limit
: 0.2 mm (0.008 in)
SEM296D
Runout (total indicator reading)
Limit
: 0.15 mm (0.0059 in)
AEM328
CYLINDER HEAD
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VALVE GUIDE CLEARANCE
1.
Measure valve deflection as shown. Valve and valve guide
mostly wear in this direction.
2.
If the valve exceeds the deflection limit, check the valve to valve
guide clearance:
a.
Measure valve stem diameter and valve guide inner diameter.
b.
Check that clearance is within specification.
Valve to valve guide clearance = valve guide inner diameter
- valve stem diameter.
Unit: mm (in)
c.
If the clearance exceeds the limit, replace the valve and remea-
sure the clearance.
d.
If the clearance still exceeds the limit after replacing the valve,
replace the valve guide.
VALVE GUIDE REPLACEMENT
1.
To remove the valve guide, heat the cylinder head to 120
° -
140
°C (248° - 284°F) by soaking in heated oil.
Valve deflection limit (dial gauge reading)
Intake & Exhaust
: 0.2 mm (0.008 in)
SEM297D
Valve
Standard
Limit
Intake
0.020 - 0.053 (0.0008 - 0.0021)
0.08 (0.0031)
Exhaust
0.040 - 0.073 (0.0016 - 0.0029)
0.1 (0.004)
SEM298D
SEM008A
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CYLINDER HEAD
2.
To remove the valve guide, use a press [less than 20 kN (2 met-
ric ton, 2.2 US ton, 2.0 Imp. ton) pressure] or hammer and suit-
able tool, to slide the valve guide out of the cylinder head.
3.
Ream the cylinder head valve guide hole.
4.
Heat cylinder head to 120
° - 140°C (248° - 284°F) in heated oil
and press the replacement valve guide into the valve guide hole
in the cylinder head. Press the valve guide in to the specified
height "L" as shown.
5.
Ream the new replacement valve guide.
SEM299D
Valve guide hole diameter (for service parts)
Intake & Exhaust
: 11.175 - 11.196 mm
(0.4400 - 0.4408 in)
SEM300D
Projection “L”
: 13.3 - 13.9 mm (0.524 - 0.547 in)
SEM301D
Finished size
Intake & Exhaust
: 7.000 - 7.018 mm (0.2756 - 0.2763 in)
SEM300D
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