Nissan Frontier D40. Manual - part 584

EM-68

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CYLINDER HEAD

5.

Remove valve oil seal using Tool.

6.

When valve seat must be replaced, refer to 

EM-69, "Inspection After Disassembly"

.

7.

When valve guide must be replaced, refer to 

EM-69, "Inspection After Disassembly"

.

8.

Remove spark plug tube, if necessary.
• Remove it from cylinder head using suitable tool.

CAUTION:

• Be careful 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.

Install valve guide if removed. Refer to 

EM-69, "Inspection After Disassembly"

.

2.

Install valve seat if removed. Refer to 

EM-69, "Inspection After Disassembly"

.

3.

Install valve oil seal using Tool.

NOTE:
Install with the valve oil seal to match dimension as shown.

4.

Install valve.
NOTE:
Install larger diameter to intake side.

5.

Install valve spring (with valve spring seat).
NOTE:
• 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 using Tool.

Tool numbers

: KV10115600 (J-38958)

WBIA0478E

Tool numbers

: KV10115600 (J-38958)

Height (H)

: 11.8 - 12.4 mm (0.465 - 0.488 in)

WBIA0653E

Intake

: Pink

Exhaust

: Green

PBIC0525E

Tool numbers

: KV10116200 (J-26336-A)

: KV10115900 (J-26336-20)

CYLINDER HEAD

EM-69

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• Install valve collet with a magnet hand.

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.

9.

Install spark plug tube if removed.
• Press-fit it into cylinder head as follows:

a.

Remove old sealant from cylinder head side installation hole.

b.

Apply sealant 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-22, "Recommended Chemical Products and

Sealants"

.

c.

Press-fit spark plug tube so that its height (H) is as specified
using suitable tool.

CAUTION:

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

10. Install spark plug.

Inspection After Disassembly

INFOID:0000000005274294

VALVE DIMENSIONS

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

EM-106,

"Standard and Limit"

.

• If dimensions are out of the standard, replace valve and check the

valve seat contact.

VALVE GUIDE CLEARANCE

Valve Stem Diameter

WBIA0578E

Standard press-fit 
height (H)

: 41.2 - 42.2 mm (1.622 - 1.661 in)

PBIC2713E

SEM188A

EM-70

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CYLINDER HEAD

Measure the diameter of valve stem with micrometer.

Valve Guide Inner Diameter

Measure the inner diameter of valve guide with inside micrometer.

Valve Guide Clearance

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

• If it exceeds the limit, replace valve guide and/or valve.

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 lmp ton) force] or suitable tool.

WARNING:

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

Standard

Intake

: 5.965 - 5.980 mm (0.2348 - 0.2354 in)

Exhaust

: 5.955 - 5.970 mm (0.2344 - 0.2350 in)

SEM938C

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

CYLINDER HEAD

EM-71

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3.

Ream cylinder head valve guide hole using suitable tool.

4.

Heat cylinder head to 110

°

 to 130

°

C (230

°

 to 266

°

F) by soaking

in heated oil.

5.

Press valve guide from camshaft side to the dimensions as
shown using suitable tool.

WARNING:

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

6.

Apply reamer finish to valve guide using suitable tool.

VALVE SEAT CONTACT

Valve guide hole diameter (for service parts):

Intake and exhaust

: 10.175 - 10.196 mm (0.4006 - 0.4014 in)

SEM932C

SEM008A

Projection (H)

Intake

: 10.1 - 10.3 mm (0.398 - 0.406 in)

Exhaust

: 10.0 - 10.4 mm (0.394 - 0.409 in)

PBIC2187E

Standard

Intake and exhaust:

6.000 - 6.018 mm (0.2362 - 0.2369 in)

SEM932C