Chery Fora (Elara A520). Manual — part 162

CHERY A21 SERVICE MANUAL

MECHANISM OF 2.0NALC ENGINE

21

b:

Use internal micrometer guage to
measure the internal diameter of valve
guide and the measuring point is a
quartering point of guide.

c:

Calculate the difference of measured
value and the clearance.

Replace the valve or the guide if the value
exceeds the limit value.

d:

Examine the contact bandwidth of
valve.

e:

Check the valve seat insert.

Standard

Value

IN

￠5.98±0.008

Outer Diameter

of Valve stem

(mm)

EX

￠5.96±0.008

IN

￠5.4±0.1

Inner Diameter

of Valve guide

(mm)

EX

￠5.4±0.1

IN

0.02

Clearance

(mm)

EX

0.04

IN

0.3±0.15

Thickness of

Valve Top

（mm）

EX

0.3±0.15

IN

1.158

Seal Bandwidth

（mm）

EX

1.306

Measuring Point

Contact Position (Should be

the Center of Slope)

Edge

Thickness

CHERY A21 SERVICE MANUAL

MECHANISM OF 2.0NALC ENGINE

22

f:

Examine the protruding capacity of
valve stem.

And Examine the protruding high of valve
stem with vernier caliper.（See picture）

Standard Value（mm）

Protruding Capacity

Of Intake Valve

stem

47.5

Protruding Capacity

Of Exhaust Valve

stem

47.5

5)

Examine the axial clearance of camshaft.

Replace the camshaft if the value of axial
clearance exceeds the normal value.

Standard Value

Intake camshaft

0.015—0.02

Exhaust camshaft

0.015—0.02

6)

Examine the planeness of cylinder

a:

Clear the lower surface of cylinder head.

b:

With the help of ruler and feeler gauge,
check whether the lower surface of
cylinder head is warped.(Measure it in
the sequence of A, C, D, E, F, G in the
picture)

Standard

Value

Cylinder head planeness

0.04

Top of Valve Stem

Protruding High of Valve Stem

Seat of Valve Spring

CHERY A21 SERVICE MANUAL

MECHANISM OF 2.0NALC ENGINE

23

C:

Revise it if the planeness exceeds, and
replace when it exceeds the limit value.

The permitted maximum abrading thickness
between cylinder block and cylinder head is:

2.2.3

Installation

The installing steps are reverse to those for
removal.

Note:

1)

Dismantle valve springs into groups.
The 1st and 4th cylinders are in one
group and the 2nd and 3rd ones are in
the other group. Then put the piston to
the upper point of 1st and 4th cylinders
in order to dismantle the valve spring of
1st and 4th cylinders, replace their valve
oil

seal

and

mount

the

spring

immediately. And put the piston to the
upper point of 2nd and 3rd cylinders in
order to replace the other valve oil seal.
Those steps prevent from that the valve
falls into cylinder and the unanticipated
trouble occurs.

2)

Wipe the engine transmission oil on the
opening of oil seal when mounting the
valve oil seal.

3)

Fasten the cylinder bolt as the following
process.

A:

Smear some oil on the top and root of
bolt.

B:

Fasten to 40±5NM in sequence.

C:

Fasten 90±5 degree clockwise.

D:

Fasten 90±5 degree clockwise.

2.3 Replace thermostat

2.3.1

Structural diagram

8

4

1

5

9

7

3

2

6

10

CHERY A21 SERVICE MANUAL

MECHANISM OF 2.0NALC ENGINE

24

2.3.2 Needed tools and auxiliary materials

Hatch clamp,10# sleeve, ratchet wheel and wrench

2.3.3 Removal

1)

Loosen the clamp of thermostat water exhaust pipe with hatch clamp to release the
coolant.

Note: Do it after the temperature decreased to prevent scald.

2)

Remove the 4 bolts of thermostat cover with 10# sleeve wrench.

3)

Take out the thermostat.

2.3.4 Inspection

Put the thermostat in the boiling water and use it with thermometer. Then observe the
temperatures when the thermostat is turning on and fully opened.

Temperature value

Regular unlocking temperature

87℃

fully opened temperature

104℃

Replace the new thermostat if the measured value is abnormal.

2.3.5 Installation

The installing steps are reverse to those for removal.

Note: Fill in the engine coolant with fixed quantity after installation.

1

2

3

4

5

6

1. Pad—Thermostat Seat

2. Thermostat Seat

3. Hexagonal Flange Bolt

4. Thermostat Assembly

5. Hexagonal Flange Bolt

6. Cover—Thermostat Seat