Nissan Quest E52. Manual - part 588

CYLINDER HEAD

EM-101

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c.

Using a drift, press-fit spark plug tube so that its height (A) 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.

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

Inspection

INFOID:0000000009652797

INSPECTION AFTER REMOVAL

Cylinder Head Bolts Outer Diameter

• Cylinder head bolts are tightened by plastic zone tightening

method. Whenever the size difference between (C) and (B)
exceeds the limit, replace them with new one. 

• If reduction of outer diameter appears in a position other than (B),

use it as (B) point.

Cylinder Head Distortion

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

EM-113, "Inspec-

tion"

.

1.

Using a scraper, wipe off oil, scale, gasket, sealant and carbon deposits from surface of cylinder head.

CAUTION:

Never allow gasket fragments to enter engine oil or engine coolant passages.

2.

At each of several locations on bottom surface of cylinder head,
measure the distortion in six directions (A), (B), (C), (D), (E), and
(F).

• If it exceeds the limit, replace cylinder head.

INSPECTION AFTER DISASSEMBLY

Valve Dimensions

• Check the dimensions of each valve. For the dimensions, refer to 

EM-131, "Cylinder Head"

.

• If dimensions are out of the standard, replace valve and check valve seat contact. Refer to “Valve Seat Con-

tact”.

Valve Guide Clearance

Valve Stem Diameter

B

: Genuine high strength thread locking sealant application area

Standard press-fit height: 37.7 - 38.7 mm (1.484 - 1.524 in)

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A

: Measuring point

d

: 11 mm (0.43 in)

e

: 48 mm (1.89 in)

Limit [(C) - (B)]

: 0.11 mm (0.0043 in)

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Limit

: Refer to 

EM-131, "Cylinder Head"

.

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CYLINDER HEAD

• Measure the diameter of valve stem with micrometer (A).

Valve Guide Inner Diameter

• Measure the inner diameter of valve guide with bore gauge.

Valve Guide Clearance

• (Valve guide clearance) = (Valve guide inner diameter) – (Valve stem diameter)

• If the calculated value exceeds the limit, replace valve and/or valve guide. When valve guide must be

replaced, refer to 

EM-97, "Disassembly and Assembly"

.

Valve Seat Contact

• After confirming that the dimensions of valve guides and valves are within the 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 surface.

• Check if the contact area band is continuous all around the circumference.
• If not, grind to adjust valve fitting and check again. If the contacting

surface still has “NG” conditions (B) even after the recheck,
replace valve seat. Refer to 

EM-97, "Disassembly and Assembly"

.

Valve Spring Squareness

• Set a try square (A) along the side of valve spring and rotate

spring. Measure the maximum clearance between the top of spring
and try square.

• If it exceeds the limit, replace valve spring.

Valve Spring Dimensions and Valve Spring Pressure Load

Standard 

: Refer to 

EM-131, 

"Cylinder Head"

.

(Intake and exhaust)

Standard

: Refer to 

EM-131, 

"Cylinder Head"

.

(Intake and exhaust)

Valve guide clearance

: Refer to 

EM-131, "Cylinder Head"

.

Standard and limit (Intake and exhaust)

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A

:  OK

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B

: Contact

Limit

: Refer to 

EM-131, "Cylinder Head"

.

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CYLINDER HEAD

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• Check the valve spring pressure at specified spring height.

• If the installation load or load with valve open is out of the stan-

dard, replace valve spring.

INSPECTION AFTER INSTALLATION

Inspection for Leakage

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

• 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, "Fluids and Lubricants"

.

• Use procedure below to check for fuel leakage.
- Turn ignition switch “ON” (with engine stopped). With fuel pressure applied to fuel piping, check for fuel leak-

age 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 check there is no leakage of fuel, exhaust gases, or any oil/fluids including

engine oil and engine coolant.

• Bleed air from lines and hoses of applicable lines, such as in cooling system.
• After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to the

specified level, if necessary.

Summary of the inspection items:

*: Power steering fluid, brake fluid, etc.

Standard (Intake and exhaust)

: Refer to 

EM-131, 

"Cylinder Head"

.

Free height

Installation height

Installation load

Height during valve open

Load with valve open

SEM113

Items

Before starting engine

Engine running

After engine stopped

Engine coolant

Level

Leakage

Level

Engine oil

Level

Leakage

Level

Transmission / 
transaxle fluid

AT & CVT Models

Leakage

Level / Leakage

Leakage

MT Models

Level / Leakage

Leakage

Level / Leakage

Other oils and fluids*

Level

Leakage

Level

Fuel

Leakage

Leakage

Leakage

Exhaust gases

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Leakage

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EM-104

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CYLINDER BLOCK

CYLINDER BLOCK

Exploded View

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1.

Reinforcement plate

2.

Drive plate

3.

Rear oil seal retainer

4.

Sub harness

5.

Knock sensor 

6.

Cylinder block

7.

Thrust bearing (upper)

8.

Main bearing (upper)

9.

Crankshaft

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