Infiniti Q45. Manual - part 563

CYLINDER HEAD

EM-69

C

D

E

F

G

H

I

J

K

L

M

A

EM

4.

Remove cylinder head bolts in the reverse order shown in the
figure and using the cylinder head bolt wrench (Commercial ser-
vice tool: J-24239-01). 

5.

Remove cylinder head gaskets.

INSPECTION AFTER REMOVAL
Cylinder Head Bolts Outer Diameter 

●

Cylinder head bolts are tightened by plastic zone tightening
method. Whenever the size difference between “d1” and “d2”
exceeds the limit, replace them with new one. 

●

If reduction of outer diameter appears in a position other than
“d2”, use it as “d2” point.

Cylinder Head Distortion

NOTE:
When performing this inspection, cylinder block distortion should be also checking. Refer to 

EM-103, "CYLIN-

DER BLOCK DISTORTION"

 .

1.

Wipe off oil and remove water scale (like deposit), gasket, sealer, carbon, etc. with scraper.

CAUTION:

Use utmost care not to allow liquid gasket debris to enter passages for engine oil or engine cool-
ant.

2.

At each of several locations on bottom surface of cylinder head,
measure distortion in six directions with a straightedge and a
feeler gauge.

●

If it exceeds the limit, replace cylinder head.

INSTALLATION

1.

Install cylinder head gaskets.

2.

Turn crankshaft until No. 1 piston is set at TDC.

PBIC0068E

Limit (“d1”-“d2”)

: More than 0.18 mm (0.0071 in)

KBIA0189E

Limit

: 0.1mm (0.004 in)

PBIC0075E

EM-70

CYLINDER HEAD

●

Crankshaft key should line up with the left bank cylinder cen-
ter line as shown in the figure.

3.

Install cylinder head follow the steps below to tighten cylinder
head bolts in numerical order as shown in the figure with the cyl-
inder head bolt wrench (commercial service tool: J-24239-01).

CAUTION:

●

If cylinder head bolts are re-used, check their outer diam-
eters before installation. Refer to 

EM-69, "Cylinder Head

Bolts Outer Diameter"

 .

a.

Apply new engine oil to threads and seating surface of cylinder head bolts.

b.

Tighten all cylinder head bolts. 

c.

Completely loosen all cylinder head bolts.

CAUTION:

In step “c”, loosen cylinder head bolts in the reverse order of that indicated in the figure.

d.

Tighten all cylinder head bolts. 

e.

Turn all cylinder head bolts 60 degrees clockwise. (Angle tight-
ening)

CAUTION:

Check the tightening angle by using angle wrench (SST).
Avoid judgment by visual inspection without SST.

●

Check tightening angle indicated on angle wrench indicator
plate.

f.

Turn all cylinder head bolts 60 degrees clockwise again. (Angle
tightening)

4.

Install in the reverse order of removal.

INSPECTION AFTER INSTALLATION
inspection for Leaks

The following are procedures for checking fluids leak, lubricates leak and exhaust gases leak.

●

Before starting engine, check oil/fluid levels including engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to 

MA-10, "RECOMMENDED FLUIDS AND LUBRICANTS"

  .

●

Use procedure below to check for fuel leakage.

PBIC2389E

PBIC0068E

 : 98.1 N·m (10 kg-m, 72 ft-lb)

 : 0 N·m (0 kg-m, 0 ft-lb)

 : 44.1 N·m (4.5 kg-m, 33 ft-lb)

PBIC0069E

CYLINDER HEAD

EM-71

C

D

E

F

G

H

I

J

K

L

M

A

EM

–

Turn ignition switch “ON” (with engine stopped). With fuel pressure applied to fuel piping, check for fuel
leakage at connection points.

–

Start engine. With engine speed increased, check again for fuel leakage at connection points.

●

Run engine to check for unusual noise and vibration.

●

Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids includ-
ing engine oil and engine coolant.

●

Bleed air from passages in lines and hoses, such as in cooling system.

●

After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to
specified level, if necessary.

Summary of the inspection items:

* Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.

Item

Before starting engine

Engine running

After engine stopped

Engine coolant

Level

Leakage

Level

Engine oil

Level

Leakage

Level

Other oils and fluids *

Level

Leakage

Level

Fuel

Leakage

Leakage

Leakage 

Exhaust gas

—

Leakage

—

EM-72

CYLINDER HEAD

Disassembly and Assembly

NBS001OZ

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.

1.

Spark plug

2.

Adjusting shim

3.

Valve lifter

4.

Valve collet

5.

Valve spring retainer

6.

Valve spring (with valve spring seat)

7.

Valve oil seal

8.

Valve guide

9.

Valve seat 

10.

Valve (INT)

11.

Valve (EXH)

12.

Cylinder head (left bank)

13.

Spark plug tube

14.

Cylinder head (right bank)

PBIC2757E

PBIC2360E