Nissan ENGINE - Page 95

CYLINDER HEAD
EM-95
< REMOVAL AND INSTALLATION >
[VQ40DE]
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Valve Guide Clearance
(Valve guide clearance) = (Valve guide inner diameter) – (Valve stem diameter).
• If the calculated value exceeds the limit, replace valve and/or valve guide.
VALVE GUIDE REPLACEMENT
When valve guide is removed, replace with oversized [0.2 mm (0.008 in)] valve guide.
1. To remove valve guide, heat cylinder head to 110° to 130°C
(230° to 266°F) by soaking in heated oil.
2. Drive out valve guide with a press [under a 20 kN (2 ton, 2.2 US
ton, 2.0 Imp ton) pressure] or hammer and suitable tool.
WARNING:
Cylinder head contains heat. When working, wear protec-
tive equipment to avoid getting burned.
3. Ream cylinder head valve guide hole using suitable tool.
Standard
Intake and Exhaust : 6.000 - 6.018 mm (0.2362 - 0.2369 in)
Valve guide clearance:
Standard
Intake : 0.020 - 0.053 mm (0.0008 - 0.0021 in)
Exhaust : 0.030 - 0.063 mm (0.0012 - 0.0025 in)
Limit
Intake : 0.08 mm (0.003 in)
Exhaust : 0.09 mm (0.004 in)
SEM008A
SEM931C
Valve guide hole diameter (for service parts):
Intake and exhaust
: 10.175 - 10.196 mm (0.4006 - 0.4014 in)
SEM932C
Revision: January 2013 2013 Xterra