Nissan X-Trail 32. Manual — part 1064
STRUCTURE AND OPERATION
EM-153
< SYSTEM DESCRIPTION >
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STRUCTURE AND OPERATION
Major Kinetic System
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DESCRIPTION
• The adoption of the following items enables high-compression by controlling the knocking without increasing
the temperature in the combustion chamber:
- Sodium-filled exhaust valves: Releases heat from the combustion chamber. For details, refer to
• The coating of hydrogen-free DLC to the valve lifter and the piston ring enables low friction.
NOTE:
Hydrogen-free DLC (Diamond-like Carbon) coating: Coating by the Ion-plating method without using carbon-
free graphite as the evaporation source. This improves the adherence with engine oil and significantly
reduces the friction coefficient.
STRUCTURE
EM-154
< SYSTEM DESCRIPTION >
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STRUCTURE AND OPERATION
JSBIA3306ZZ
Camshaft bracket (No.1)
Rocker cover
Oil filler cap
Camshaft position sensor bracket
Rocker cover gasket
Cylinder head
Gasket
Rear oil seal
Cylinder block
Balancer unit
Oil pan (upper)
Oil pan (lower)
Drain plug washer
Drain plug
Top ring
STRUCTURE AND OPERATION
EM-155
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Valve System
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DESCRIPTION
• The valve system has the DOHC mechanism with the V-shaped valve layout and the cam shaft is driven by
the single-stage chain system.
• The adoption of a small-pitch silent chain with a lighter and more compact cam shaft drive system (e.g. use
of smaller sprocket) reduces noise generated from the drive system.
• The adoption of sodium-filled exhaust valves reduces the valve
temperature and improves the intake efficiency. The stem of this
valve is hollow and includes metallic sodium with larger specific
heat (large absorbed duty). Metallic sodium is liquefied at tempera-
tures while the vehicle is traveling.
NOTE:
With the sodium-filled exhaust valves, metallic sodium is agitated
by the open-close motion of the valve, and the heat generated in
the combustion chamber and exhaust port is released to the valve
guide to reduce the temperature of the valve umbrella.
• The adoption of the single beehive spring for the valve spring
reduces friction and prevents spring surge.
• The adoption of the intake valve timing control and the exhaust valve timing control enables the continuous
adjustment of the valve timing within the movable range by oil pressure. This can control the optimum valve
timing according to engine speeds and load, allowing significant improvement in low/intermediate torque.
• The adoption of the intake manifold intermediate lock control reduces HC at a cold start.
For details on control, refer to the following information:
• Intake valve timing control:
EC-466, "INTAKE VALVE TIMING CONTROL : System Description"
• Exhaust valve timing control:
EC-469, "EXHAUST VALVE TIMING CONTROL : System Description"
STRUCTURE
Second ring
Oil ring
Piston pin
Piston
Connecting rod
Connecting rod bearing
Connecting rod cap
Oil jet
Thrust bearing
Main bearing (upper)
Crankshaft
Crankshaft key
Main bearing (lower)
Lower cylinder block
Front cover
Valve timing control cover
Front oil seal
Crankshaft pulley
JSBIA1699GB
JSBIA1700GB
EM-156
< SYSTEM DESCRIPTION >
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STRUCTURE AND OPERATION
Chain tensioner (for timing chain)
Timing chain slack guide
Camshaft sprocket (INT)
Camshaft sprocket (EXH)
Timing chain
Timing chain tension guide
Crankshaft sprocket
Oil pump sprocket
Oil pump drive chain
Chain tensioner (for oil pump drive
chain)
Camshaft bracket (No.1)
Camshaft bracket
Camshaft (INT)
Camshaft (EXH)
Valve lifter
Valve collet
Valve spring retainer
Valve spring
Valve oil seal
Valve guide
Cylinder head
Valve seat (EXH)
Valve (EXH)
Valve (INT)
Valve seat (INT)
JSBIA3307ZZ
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