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Nissan Altima L32. Manual - part 665

EM-196

< ON-VEHICLE REPAIR >

[VQ35DE]

CYLINDER HEAD

DISASSEMBLY

1. Remove spark plug.
2. Remove valve lifter.

• Identify installation positions, and store them without mixing them up.

3. Remove valve collet.

• Compress valve spring and remove valve collet with magnet

hand using Tool.

CAUTION:

When working, take care not to damage valve lifter holes.

4. Remove valve spring retainer, valve spring and valve spring seat.
5. Push valve stem to combustion chamber side, and remove valve.

• Identify installation positions, and store them without mixing them up.

6. Remove valve oil seals using Tool.

7. If valve seat must be replaced, refer to

EM-197, "Inspection After Disassembly"

8. If valve guide must be replaced, refer to

EM-197, "Inspection After Disassembly"

9. Remove spark plug tube, as necessary.

• Using pair of pliers, pull spark plug tube out of cylinder head.

CAUTION:

• Take care not to damage cylinder head.

• Once removed, spark plug tube will be deformed and cannot be reused. Do not remove it unless

absolutely necessary.

ASSEMBLY

1. When valve guide is removed, install it. Refer to

EM-197, "Inspection After Disassembly"

2. When valve seat is removed, install it. Refer to

EM-197, "Inspection After Disassembly"

3. Install valve oil seals using Tool.

4. Install valve spring seat.
5. Install valves.

• Install it in the original position.

NOTE:

Larger diameter valves are for intake side.

Tool numbers

: KV10109230 (

—

)

: KV10116200 (J-26336-A)
: KV10115900 (J-26336-20)

WBIA0578E

Tool number

: KV10107902 (J-38959)

WBIA0489E

Tool number

—

(J-39386)

Height (H) (Without valve spring seat installed)

Intake and exhaust

: 14.3 - 14.9 mm (0.563 - 0.587 in)

WBIA0490E

CYLINDER HEAD

EM-197

< ON-VEHICLE REPAIR >

[VQ35DE]

6. Install valve spring (uneven pitch type) with narrow pitch end

(paint mark) to cylinder head side (valve spring seat side).

7. Install valve spring retainer.
8. Install valve collet.

• Compress valve spring with valve spring compressor, attach-

ment and adapter using Tool. Install valve collet with magnet

hand.

CAUTION:

When working, take care not to damage valve lifter holes.

• Tap valve stem edge lightly with plastic hammer after installa-

tion to check its installed condition.

9. Install valve lifter.

• Install it in the original position.

10. Install spark plug tube.

• Press-fit spark plug tube as follows:

a. Remove old liquid gasket adhering to cylinder head mounting hole.
b. Apply sealant to area within approximately 12 mm (0.47 in) from edge of spark plug tube press-fit side.

Use Genuine High Strength Locking Sealant or equivalent. Refer to

GI-15, "Recommended Chemi-

cal Products and Sealants"

c. Press-fit spark plug tube so that its height (H) is as specified in

using suitable drift.

CAUTION:

• When press-fitting, take care not to deform spark plug

tube.

• After press-fitting, wipe off liquid gasket protruding onto

cylinder-head upper face.

11. Install spark plug.

Inspection After Disassembly

INFOID:0000000004202180

CYLINDER HEAD DISTORTION

Clean the surface of the cylinder head. Use a reliable straightedge and feeler gauge to check the flatness of

cylinder head surface.

SEM085D

Tool numbers

: KV10109230 (

—

)

: KV10116200 (J-26336-A)
: KV10115900 (J-26336-20)

WBIA0578E

Press-fit height (H)

: 37.7 - 38.7 mm (1.484 - 1.529 in)

PBIC2638E

EM-198

< ON-VEHICLE REPAIR >

[VQ35DE]

CYLINDER HEAD

Check along six positions as shown.

If beyond the specified limit, resurface or replace it.

The limit for cylinder head resurfacing is determined by the cyl-

inder block resurfacing.

After resurfacing cylinder head, check that camshaft rotates freely by hand. If resistance is felt, cylinder head

must be replaced.

VALVE GUIDE CLEARANCE

1. Measure valve deflection as shown. (Valve and valve guide

mostly wear in this direction.)

2. If it exceeds the limit, check valve to valve guide clearance.
a. Measure valve stem diameter and valve guide inner diameter.

Refer to

EM-229, "Camshaft"

b. Check that clearance is within specification.

(Valve guide clearance) = (Valve guide inner diameter) - (Valve

stem diameter)

If it exceeds the limit, replace valve or valve guide.

VALVE GUIDE REPLACEMENT

When valve guide is removed, replace with oversized [0.2 mm (0.008 in)] valve guide.

Head surface distortion
Limit

: 0.1 mm (0.004 in)

Standard

: Less than 0.03 mm
(0.0012 in)

Resurfacing Limit
Amount of cylinder head resurfacing is (A).
Amount of cylinder block resurfacing is (B).
The maximum limit

: A + B = 0.2 mm (0.008 in)

Nominal cylinder head height

: 126.3 - 126.5 mm (4.972 - 4.980 in)

SEM861E

Valve deflection limit (dial gauge reading)
Intake

: 0.24 mm (0.0094 in)

Exhaust

: 0.28 mm (0.0110 in)

SEM178F

Valve to valve guide clearance standard
Intake

: 0.020 - 0.053 mm (0.0008 - 0.0021 in)

Exhaust

: 0.040 - 0.073 mm (0.0016 - 0.0029 in)

Valve to valve guide clearance limit
Intake

: 0.08 mm (0.0031 in)

Exhaust

: 0.1 mm (0.004 in)

SEM938C

CYLINDER HEAD

EM-199

< ON-VEHICLE REPAIR >

[VQ35DE]

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 the valve guide with a press [under a 20 kN (2.2 US

ton) pressure] or hammer and suitable tool.

3. Ream cylinder head valve guide hole.

4. Heat cylinder head to 110

° to 130°C (230° to 266°F) by soaking

in heated oil and press new valve guide from camshaft side into

the cylinder head to the dimensions as shown.

SEM008A

SEM931C

Valve guide hole diameter
(for service parts), intake
and exhaust

: 10.175 - 10.196 mm
(0.4006 - 0.4014 in)

SEM932C

Projection (L)

: 12.6 - 12.8 mm (0.496 - 0.504 in)

SEM950E

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