Infiniti G37 Coupe. Manual - part 610

SPARK PLUG

EM-15

< ON-VEHICLE MAINTENANCE >

C

D

E

F

G

H

I

J

K

L

M

A

EM

N

P

O

SPARK PLUG

Exploded View

INFOID:0000000001547615

Removal and Installation

INFOID:0000000001547616

REMOVAL

1.

Remove engine cover with power tool. Refer to 

EM-28, "Exploded View"

.

2.

Remove air cleaner case and air duct (RH and LH). Refer to 

EM-26, "Exploded View"

.

3.

Remove electric throttle control actuator. Refer to 

EM-31, "Exploded View"

.

4.

Remove ignition coil. Refer to 

EM-45, "Removal and Installation"

.

1.

PCV hose

2.

Clamp

3.

PCV valve

4.

O-ring

5.

Clamp

6.

PCV hose

7.

Ignition coil

8.

Spark plug

9.

Rocker cover (bank 1)

10.

Oil filler cap

11.

Oil catcher

12. Rocker cover gasket (bank 1)

13.

Clamp

14.

PCV hose

15. PCV valve

16.

PCV hose

17.

Clamp

18. Rocker cover gasket (bank 2)

19.

Rocker cover (bank 2)

20.

Spark plug

21. Ignition coil

A.

To intake manifold collector

B.

To air duct

C.

VVEL ladder assembly side

D.

Refer to 

EM-45

Refer to 

GI-4, "Components"

 for symbols in the figure.

JPBIA1174GB

EM-16

< ON-VEHICLE MAINTENANCE >

SPARK PLUG

5.

Remove spark plug with a spark plug wrench (commercial ser-
vice tool).

INSTALLATION

Installation is the reverse order of removal.

Inspection

INFOID:0000000001547617

INSPECTION AFTER REMOVAL

Use the standard type spark plug for normal condition.

CAUTION:

• Never drop or shock spark plug.
• Never use a wire brush for cleaning.
• If plug tip is covered with carbon, use spark plug cleaner to

clean.

• Check and adjustment of plug gap is not required between

change intervals.

a

: 14 mm (0.55 in)

JPBIA0030ZZ

Spark plug (Standard type)

: Refer to 

EM-138, "Spark Plug"

.

Cleaner air pressure

: Less than 588 kPa (6 kg/cm

2

, 85 psi)

Cleaning time

: Less than 20 seconds

SMA773C

JPBIA0031ZZ

CAMSHAFT VALVE CLEARANCE

EM-17

< ON-VEHICLE MAINTENANCE >

C

D

E

F

G

H

I

J

K

L

M

A

EM

N

P

O

CAMSHAFT VALVE CLEARANCE

Inspection and Adjustment

INFOID:0000000001547618

INSPECTION

Check valve clearance if applicable to the following cases:

Intake side:

• At the removal and installation of VVEL ladder assembly or valve-related parts, or at the occurrence of mal-

function (poor starting, idle malfunction, unusual noise) due to aged deterioration in valve clearance.

CAUTION:

Valve clearance check on the intake side is not required after replacing the VVEL ladder assembly &
cylinder head assembly with a new one. (Install new VVEL ladder assembly & cylinder head assembly
in factory-shipped condition because it is factory-adjusted and inspected.)
NOTE:
VVEL ladder assembly cannot be replaced as a single part, because it is machined together with cylinder
head assembly.

Exhaust side:

• At the removal, installation, and replacement of camshaft (EXH) or valve-related parts, or at the occurrence

of malfunction (poor starting, idle malfunction, unusual noise) due to aged deterioration in valve clearance.

1.

Remove rocker covers (bank 1 and bank 2). Refer to 

EM-45, "Removal and Installation"

.

2.

Measure the valve clearance as follows:
• Use the feeler gauge (commercial service tool) of curved-tip. This allows the feeler gauge to access the

clearance between camshaft and valve lifter with ease.

NOTE:
Be sure to note the following points when measuring valve clearance on the intake side.
• Before measuring, check that the position of drive shaft nose

is within the angle shown in the figure.

• Refer to the illustration for the insertion direction of the feeler

gauge since the direction depends on the bank.

a.

Set No. 1 cylinder at TDC of its compression stroke.

Valve clearance

: Refer to 

EM-139, "Camshaft"

.

A

:  Bank  1

B

: Feeler gauge (commercial service tool)

c

: 45 degrees (drive shaft nose angle)

D

:  View

: Insertion direction of feeler gauge on the bank 1

: Insertion direction of feeler gauge on the bank 2

JPBIA1118ZZ

EM-18

< ON-VEHICLE MAINTENANCE >

CAMSHAFT VALVE CLEARANCE

• Rotate crankshaft pulley clockwise to align timing mark

(grooved line without color) with timing indicator.

• Check that exhaust cam nose on No. 1 cylinder (engine front

side of bank 1) is located as shown in the figure.

• If not, turn crankshaft one revolution (360 degrees) and align

as shown in the figure.

• By referring to the figure, measure the valve clearances at

locations marked “

×

” as shown in the table below (locations

indicated in the figure).

• No. 1 cylinder at compression TDC

b.

Rotate crankshaft 240 degrees clockwise (when viewed from engine front) to align No. 3 cylinder at TDC
its compression stroke.
NOTE:

: Timing mark (grooved line without color)

JPBIA0043ZZ

1

: Camshaft (EXH) (bank 1)

: Engine front

JPBIA1127ZZ

: Engine front

Measuring position [bank 1 (A)]

No. 1 CYL.

No. 3 CYL. 

No. 5 CYL.

No. 1 cylinder at com-

pression TDC

EXH

×

 (C)

INT

×

 (D)

Measuring position [bank 2 (B)]

No. 2 CYL.

No. 4 CYL.

No. 6 CYL.

No. 1 cylinder at com-

pression TDC

INT

×

 (E)

EXH

×

 (F)

JPBIA1334ZZ