Infiniti Q45. Manual - part 564

CYLINDER HEAD

EM-73

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6.

Remove valve oil seal with the valve oil seal puller (SST).

7.

If valve seat must be replaced, refer to 

EM-77, "VALVE SEAT REPLACEMENT"

 .

8.

If valve guide must be replaced, refer to 

EM-75, "VALVE GUIDE REPLACEMENT"

 .

9.

Remove spark plug tube, as necessary.

●

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

CAUTION:

●

Take care not to damage cylinder head.

●

Once removed, a 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-75, "VALVE GUIDE REPLACEMENT"

 .

2.

When valve seat is removed, install it. Refer to 

EM-77, "VALVE SEAT REPLACEMENT"

 .

3.

Install valve oil seal.

●

Apply new engine oil on valve oil seal joint and seal lip.

●

Install with the valve oil seal drift (SST) to match dimension in
figure.

4.

Install valve.

●

Install in the original position.

●

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.

6.

Install valve spring retainer.

PBIC0072E

PBIC0073E

PBIC0074E

EM-74

CYLINDER HEAD

7.

Install valve collet.

●

Compress valve spring with the valve spring compressor,
attachment and adapter (SST). Install valve collet with mag-
netic hand.

CAUTION:

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

●

Tap stem edge lightly with plastic hammer after installation to
check its installed condition.

8.

Install valve lifter and adjusting shim.

●

Install in the original position.

9.

Install spark plug tube as follows:

●

Press-fit spark plug tube following procedure below.

a.

Remove old liquid gasket adhering to cylinder head mounting
hole.

b.

Apply liquid gasket 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-45, "RECOMMENDED CHEMICAL PRODUCTS

AND SEALANTS"

 .

c.

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

CAUTION:

●

When press-fitting spark plug tube, take care not to deform it.

●

After press-fitting, wipe off liquid gasket protruding onto cylinder head upper face.

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

Inspection After Disassembly

NBS001P0

VALVE DIMENSIONS

●

Check dimensions of each valve. For dimensions, refer to 

EM-

111, "Valve Dimensions"

 .

●

If the dimensions are out of the standard, replace valve and
check the valve seat contact. Refer to 

EM-76, "VALVE SEAT

CONTACT"

 .

PBIC2360E

Standard press-fit height “H”:

38.4 - 39.4 mm (1.512 - 1.551 in)

PBIC2638E

SEM188A

CYLINDER HEAD

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VALVE GUIDE CLEARANCE
Valve Stem Diameter

Measure diameter of valve stem with micrometer.

Valve Guide Inner Diameter

Measure 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 and/or valve guide.

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) pressure] or hammer and the valve guide drift
(commercial service tool).

WARNING:

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

Standard

Intake

: 5.972 - 5.980 mm (0.2351 - 0.2354 in)

Exhaust

: 5.962 - 5.970 mm (0.2347 - 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 - 0.046 mm (0.0008 - 0.0018 in)

Exhaust

: 0.030 - 0.056 mm (0.0012 - 0.0022 in)

Limit

Intake

: 0.08 mm (0.003 in)

Exhaust

: 0.10 mm (0.004 in)

SEM008A

SEM931C

EM-76

CYLINDER HEAD

3.

Using the valve guide reamer (commercial service tool), ream
cylinder head valve guide hole.

4.

Heat cylinder head to 110 to 130

°

C (230 to 266

°

F) by soaking in

heated oil.

5.

Using the valve guide drift (commercial service tool), press valve
guide from the camshaft side to dimensions as in the figure.

WARNING:

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

6.

Using the valve guide reamer (commercial service tool), apply
reamer finish to valve guide.

VALVE SEAT CONTACT

●

After confirming that the dimensions of valve guides and valves
are within specifications, perform this procedure. 

●

Apply prussian blue (or white lead) onto contacting surface of
valve seat to check the condition of the valve contact on the sur-
face.

●

Check if the contact area band is continuous all around the cir-
cumference.

Valve guide hole diameter (for service parts)

Intake and exhaust:

10.175 - 10.196 mm (0.4006 - 0.4014 in)

SEM932C

SEM008A

PBIC0078E

Standard

Intake and exhaust:

 6.000 - 6.018 mm (0.2362 - 0.2369 in)

SEM932C

SBIA0322E