Infiniti M45 (Y34). Manual - part 533

CYLINDER HEAD

EM-69

C

D

E

F

G

H

I

J

K

L

M

A

EM

DISASSEMBLY

1.

Remove spark plug with the spark plug wrench (commercial service tool).

2.

Remove adjusting shim and valve lifter.

●

Confirm installation point and keep parts in an organized way to avoid mixing them up.

3.

Remove valve collet. 

●

Compress valve spring with the valve spring compressor,
attachment and adapter (SST). Remove valve collet with
magnetic hand.

CAUTION:

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

4.

Remove valve spring retainer and valve spring (with valve spring seat).

CAUTION:

Do not remove valve spring seat from valve spring.

5.

Push valve stem to combustion chamber side, and remove valve. 

●

Confirm installation point and keep parts in an organized way to avoid mixing then up.

6.

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

7.

If valve guide must be replaced, refer to 

EM-71, "VALVE GUIDE REPLACEMENT"

 .

8.

If valve seat must be replaced, refer to 

EM-73, "VALVE SEAT 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-71, "VALVE GUIDE REPLACEMENT"

 .

2.

When valve seat is removed, install it. Refer to 

EM-73, "VALVE SEAT REPLACEMENT"

 .

3.

Install valve oil seal.

●

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

4.

Install valve.

●

Install larger diameter to intake side.

PBIC2360E

PBIC0072E

PBIC0073E

EM-70

CYLINDER HEAD

5.

Install valve spring (with valve spring seat).

●

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

6.

Install valve spring retainer.

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.

9.

Install spark plug tube.

●

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 RTV Silicone Sealant or equivalent. Refer to 

GI-

46, "RECOMMENDED CHEMICAL PRODUCTS AND SEAL-
ANTS"

 .

c.

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

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.

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

PBIC0074E

PBIC2360E

Standard press-fit height “H” :

: 38.4 - 39.4 mm (1.512 - 1.551 in)

KBIA1248E

CYLINDER HEAD

EM-71

C

D

E

F

G

H

I

J

K

L

M

A

EM

Inspection After Disassembly

ABS000LZ

VALVE DIMENSIONS

●

Check dimensions of each valve. For dimensions, refer to

EM-

109, "Valve Dimensions"

 .

●

If dimensions are out of the standard, replace valve.

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.

SEM188A

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)

EM-72

CYLINDER HEAD

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).

CAUTION:

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

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.

Press valve guide from the camshaft side to dimensions as in
the illustration.

CAUTION:

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

SEM008A

SEM931C

Valve guide hole diameter (for service parts)

Intake and exhaust

: 10.175 - 10.196 mm (0.4006 - 0.4014 in)

SEM932C

SEM008A

PBIC0078E