Nissan X-Trail 32. Manual — part 1085

CYLINDER HEAD

EM-237

< UNIT DISASSEMBLY AND ASSEMBLY >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EM

N

P

O

c.

Press valve guide

from camshaft side to dimensions as

shown in the figure.

CAUTION:

Cylinder head contains heat, when working, wear protective
equipment to avoid getting burned.

d.

Apply reamer finish to valve guide with a valve guide reamer
(commercial service tool) (A).

2.

Install valve seat if removed.

CAUTION:

Replace with oversize [0.5 mm (0.020 in)] valve seat.

a.

Ream cylinder head

recess diameter for service valve seat.

• Be sure to ream in circles concentric to the valve guide center.

This will enable valve seat to fit correctly.

b.

Heat cylinder head to 110 to 130

°

C (230 to 266

°

F) by soaking in

heated oil

.

c.

Provide valve seats cooled well with dry ice. Press-fit valve seat into cylinder head.

CAUTION:

• Avoid directly to touching cold valve seats.
• Cylinder head contains heat, when working, wear protective equipment to avoid getting burned.

:Cylinder head

Projection “H”

: Refer to

EM-277, "Cylinder Head"

.

PBIC3217J

Standard

: Refer to

EM-277, "Cylinder Head"

.

JSBIA2468ZZ

: Valve seat

For service parts

: Oversize [0.5 mm (0.020 in)]

Refer to

EM-277, "Cylinder Head"

.

PBIC3218J

PBIC3214J

EM-238

< UNIT DISASSEMBLY AND ASSEMBLY >

[QR25DE]

CYLINDER HEAD

d.

Using valve seat cutter set (commercial service tool) (A) or valve
seat grinder, finish valve seat to the specified dimensions. For
dimensions, refer to

EM-277, "Cylinder Head"

.

CAUTION:

When using valve seat cutter, firmly grip the cutter handle
with both hands. Then, press on the contacting surface all
around the circumference to cut in a single drive. Improper
pressure on with the cutter or cutting many different times
may result in stage valve seat.

e.

Using compound, grind to adjust valve fitting.

f.

Check again for normal contact. Refer to

EM-239, "Inspection"

.

3.

Install valve oil seal.
• Install with a valve oil seal drift [SST: KV10115600] (A) to

match dimension in the figure.
NOTE:
Dimension “H” is height that measured before installing valve
spring (with valve spring seat).

4.

Install valve.
• Install larger diameter to intake side.

5.

Install valve spring (with valve spring seat).
• Install smaller pitch (valve spring seat side) to cylinder head

side .

• Confirm identification color

of valve spring.

6.

Install valve spring retainer.

7.

Install valve collet.
• Compress valve spring with valve spring compressor [SST:

KV10116200] (A), adapter [SST: KV10109220] (B) and attach-
ment [SST: KV10115900] (C).

CAUTION:

When working, be careful not to damage valve lifter holes.

• Tap valve stem edge lightly with a plastic hammer after instal-

lation to check its installed condition.

8.

Install valve lifter.
• Install it in the original position.

JSBIA2471ZZ

Height “H”

: 11.8 - 12.4 mm (0.465 - 0.488 in)

ALBIA0864GB

: Valve spring seat

Intake

: White

Exhaust

: Light blue

JPBIA4479ZZ

JPBIA1365ZZ

CYLINDER HEAD

EM-239

< UNIT DISASSEMBLY AND ASSEMBLY >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EM

N

P

O

9.

Install spark plug tube if removed.
• Press-fit it into cylinder head with the following procedure:

a.

Remove old thread locking sealant from cylinder head side
installation hole.

b.

Apply thread locking sealant all round on spark plug tube within
approximately 12 mm (0.47 in) (A) width from edge of spark plug
tube on the press-fit side.
Use Genuine Thread Locking Sealant or equivalent.

c.

Using a drift, press-fit spark plug tube so that height is as same
as “H” shown in figure.

CAUTION:

• When press-fitting, be careful not to deform spark plug tube.
• After press-fitting, wipe off any protruding thread locking sealant on top surface of cylinder

head.

10. Install spark plug with spark plug wrench (commercial service tool).

Inspection

INFOID:0000000010783818

INSPECTION AFTER REMOVAL

Cylinder Head Bolts Outer Diameter

• Cylinder head bolts are tightened by plastic zone tightening

method. Whenever the size difference between “d1” and “d2”
exceeds the limit, replace them with a new one.

• If reduction of outer diameter appears in a position other than “d2”,

use it as “d2” point.

Cylinder Head Distortion

NOTE:
When performing this inspection, cylinder block distortion should be also checking. Refer to

EM-256, "Inspec-

tion"

.

1.

Using a scraper, wipe off oil, scale, gasket, sealant and carbon deposits from surface of cylinder head.

CAUTION:

Never allow gasket fragments to enter engine oil or engine coolant passages.

2.

At each of several locations on bottom surface of cylinder head,
measure the distortion in six directions.

• If it exceeds the limit, replace cylinder head.

VALVE DIMENSIONS

• Check dimensions of each valve. For dimensions, refer to

EM-277, "Cylinder Head"

.

• If dimensions are out of the standard, replace valve.

Standard press-fit height “H”:

41.2 - 42.2 mm (1.622 - 1.661 in)

ALBIA0870GB

Limit (“d1” – “d2”): 0.23 mm (0.0091 in)

JSBIA2565GB

A

: Straightedge

B

: Feeler gauge

Limit

: Refer to

EM-277, "Cylinder Head"

.

JSBIA2474ZZ

EM-240

< UNIT DISASSEMBLY AND ASSEMBLY >

[QR25DE]

CYLINDER HEAD

VALVE GUIDE CLEARANCE

Valve Stem Diameter

Measure the diameter of valve stem with a micrometer (A).

Valve Guide Inner Diameter

Measure the inner diameter of valve guide with a bore gauge.

Valve Guide Clearance

(Valve guide clearance) = (Valve guide inner diameter) – (Valve stem diameter).

• If it exceeds the limit, replace valve guide and/or valve. When valve guide must be replaced. Refer to

EM-

234, "Disassembly and Assembly"

.

VALVE SEAT CONTACT

• After confirming that the dimensions of valve guides and valves are within specifications, perform this proce-

dure.

• Apply prussian blue (or white lead) onto contacting surface of valve seat to check the condition of the valve

contact on the surface.

• Check if the contact area band is continuous all around the circum-

ference.

• If not, grind to adjust valve fitting and check again. If the contacting

surface still has NG conditions even after the re-check, replace
valve seat. Refer to

EM-234, "Disassembly and Assembly"

.

VALVE SPRING SQUARENESS

• Set try square (A) along the side of valve spring and rotate the

spring. Measure the maximum clearance

between the top of

valve spring and try square.

CAUTION:

Never remove valve spring seat from valve spring.

• If it exceeds the limit, replace valve spring (with valve spring seat).

VALVE SPRING DIMENSIONS AND VALVE SPRING PRESSURE LOAD

Standard

: Refer to

EM-277, "Cylinder Head"

.

JPBIA0183ZZ

Standard

: Refer to

EM-277, "Cylinder Head"

.

Standard and Limit

: Refer to

EM-277, "Cylinder Head"

.

: OK

: NG

JPBIA0187ZZ

: Contact

C

: V-block

Limit

: Refer to

EM-277, "Cylinder Head"

.

JSBIA4163ZZ