Nissan X-Trail 32. Instruction - part 1064

STRUCTURE AND OPERATION

EM-153

< SYSTEM DESCRIPTION >

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STRUCTURE AND OPERATION

Major Kinetic System

INFOID:0000000010783761

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 

EM-155,

"Valve System"

.

• 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

< SYSTEM DESCRIPTION >

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Valve System 

INFOID:0000000010783762

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