Infiniti QX56 (Z62). Manual - part 660

EM-80

< REMOVAL AND INSTALLATION >

CAMSHAFT

• (Oil clearance) = [VVEL ladder assembly (exhaust side) inner diameter] – [Exhaust camshaft journal diame-

ter].

• If the calculated value exceeds the limit, replace either or both exhaust camshaft and VVEL ladder assembly

& cylinder head assembly.
NOTE:
VVEL ladder assembly cannot be replaced as a single part, because it is machined together with cylinder
head assembly.

Exhaust Camshaft End Play

• Install a dial indicator in thrust direction on front end of camshaft.

Measure the end play of a dial indicator when exhaust camshaft is
moved forward/backward (in direction of axis).

• Measure the following parts if out of the limit.
- Dimension “A” for exhaust camshaft No. 1 journal

- Dimension “B” for cylinder head No. 1 journal bearing

• Refer to the standards above, and then replace exhaust camshaft

and/or VVEL ladder assembly & cylinder head assembly.
NOTE:
Cylinder head assembly cannot be replaced as a single part,
because it is machined together with VVEL ladder assembly.

Exhaust Camshaft Sprocket Runout

1.

Put V-block on precise flat table, and support No. 2 and 5 journals of exhaust camshaft.

CAUTION:

Never support No. 1 journal (on the side of camshaft sprocket) because it has a different diameter
from the other four locations.

2.

Measure the exhaust camshaft sprocket runout with a dial indi-
cator. (Total indicator reading)

3.

If it exceeds the limit, replace exhaust camshaft sprocket.

Valve Lifter (EXH)

Standard and limit

: Refer to 

EM-133, "Camshaft"

.

Standard and limit

: Refer to 

EM-133, "Camshaft"

.

SEM864E

Standard

: 30.500 - 30.548 mm (1.2008 - 1.2027 in)

Standard

: 30.360 - 30.385 mm (1.1953 - 1.1963 in)

JPBIA3516ZZ

Limit

: Refer to 

EM-133, "Camshaft"

.

PBIC0930E

CAMSHAFT

EM-81

< REMOVAL AND INSTALLATION >

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• Check if surface of valve lifter has any wear or crack.
• If wear or crack is found, replace valve lifter (EXH). Refer to 

EM-

133, "Camshaft"

.

Valve Lifter Clearance (EXH)

VALVE LIFTER OUTER DIAMETER

• Measure the outer diameter at 1/2 height of valve lifter with a

micrometer (A) since valve lifter is in barrel shape.

VALVE LIFTER HOLE DIAMETER

• Measure the inner diameter of valve lifter hole of cylinder head with

an inside micrometer.

VALVE LIFTER CLEARANCE

• (Valve lifter clearance) = (Valve lifter hole diameter) – (Valve lifter outer diameter)

• If the calculated value is out of the standard, referring to each standard of valve lifter outer diameter and

valve lifter hole diameter, replace either or both valve lifter and VVEL ladder assembly & cylinder head
assembly.
NOTE:
Cylinder head assembly cannot be replaced as a single part, because it is machined together with VVEL lad-
der assembly.

INSPECTION AFTER DISASSEMBLY (INTAKE SIDE)

Drive Shaft End Play

KBIA0182E

Standard

: Refer to 

EM-133, "Camshaft"

.

JPBIA0125ZZ

Standard

: Refer to 

EM-133, "Camshaft"

.

SEM867E

Standard

: Refer to 

EM-133, "Camshaft"

.

EM-82

< REMOVAL AND INSTALLATION >

CAMSHAFT

• Install a dial indicator in thrust direction on front end of drive shaft.

Measure the end play of a dial indicator when drive shaft is moved
forward/backward (in direction of axis).

• Measure the following parts if out of the limit.

- Dimension “A” for drive shaft No. 1 journal

- Dimension “B” for cylinder head No. 1 journal bearing

• If it exceeds the limit, replace VVEL ladder assembly & cylinder

head assembly.
NOTE:
Cylinder head assembly cannot be replaced as a single part, because it is machined together with VVEL lad-
der assembly.

Camshaft Sprocket (INT) Runout

1.

Put V-block on precise flat table, and support No. 2 and 5 journals of drive shaft.

CAUTION:

Never support No. 1 journal (on the side of camshaft sprocket) because it has a different diameter
from the other four locations.

2.

Measure the camshaft sprocket (INT) runout with a dial indicator. (Total indicator reading)

3.

If it exceeds the limit, replace camshaft sprocket (INT).

Valve Lifter (INT)

• Check if surface of valve lifter has any wear or crack.
• If wear or crack is found, replace VVEL ladder assembly & cylinder

head assembly. Refer to 

EM-133, "Camshaft"

.

NOTE:
Since the valve lifter (INT) cannot be replaced by the piece, VVEL
ladder assembly & cylinder head assembly replacement are
required.

Valve Lifter Clearance (INT)

VALVE LIFTER OUTER DIAMETER

: Engine front

Standard and limit

: Refer to 

EM-133, "Camshaft"

.

JPBIA3517ZZ

: Engine front

Standard

: 30.500 - 30.548 mm (1.2008 - 1.2027 in)

Standard

: 30.360 - 30.385 mm (1.1953 - 1.1963 in)

JPBIA3516ZZ

Limit

: Refer to 

EM-133, "Camshaft"

.

KBIA0182E

CAMSHAFT

EM-83

< REMOVAL AND INSTALLATION >

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• Measure the outer diameter at 1/2 height of valve lifter (INT) with a

micrometer (A) since valve lifter is in barrel shape.

VALVE LIFTER HOLE DIAMETER

• Measure the inner diameter of valve lifter hole of cylinder head with

an inside micrometer.

VALVE LIFTER CLEARANCE

• (Valve lifter clearance) = (Valve lifter hole diameter) – (Valve lifter outer diameter)

• If the calculated value is out of the standard, replace VVEL ladder assembly & cylinder head assembly.

NOTE:
Since the valve lifter (INT) cannot be replaced by the piece, VVEL ladder assembly & cylinder head assem-
bly replacement are required.

VVEL Ladder Assembly

DRIVE SHAFT OPERATIONAL CHECK

• Hold the both ends of the drive shaft (A) and rotate it to check that

it rotates smoothly.

CAUTION:

Turn VVEL ladder assembly upside down to prevent the drive
shaft from dropping off.

CONTROL SHAFT OPERATIONAL CHECK

Standard

: Refer to 

EM-133, "Camshaft"

.

JPBIA0125ZZ

Standard

: Refer to 

EM-133, "Camshaft"

.

SEM867E

Standard

: Refer to 

EM-133, "Camshaft"

.

JPBIA3520ZZ