Engine 2.0 (Chery Fora, A21). Manual - part 6

CHERY A21 SERVICE MANUAL

         

MECHANISM OF 2.0NALC ENGINE 

21 

See the following picture for removal sequence of intake and exhaust camshaft-bearing caps: 

 

8)  Take out the camshaft and the hydraulic tappet. 

9)  Remove the valve spring with special tools. 

(Picture is unavailable)

 

10)  Remove the used valve oil seal with special tools. 

(Picture is unavailable) 

2.2.3

 Inspection

 

1)

 

Check the valve spring. 

Measure the free length, the verticality and 
the length under special pressure with caliper. 

 

Standard 

Value(mm)

Free length 

47.7 

Length of 

620N 

32 

Replace with the new valve spring if the 
measured value exceeds the limit value. 

 

CHERY A21 SERVICE MANUAL

         

MECHANISM OF 2.0NALC ENGINE 

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2) Check 

camshaft 

Measure the camshaft diameter with 
micrometer caliper. 

 

Standard Value

（mm） 

Limit Value 

(mm) 

Diameter 

￠24

-0.053

-0.040 

 

Replace with the new camshaft if the 
measured value exceeds the limit value.

 

 

3) Examine 

camshaft 

Measure the high of cam with micrometer 
caliper. 

 

Standard Value

（mm） 

limit value

（mm） 

Intake 

Cam 

37.15 

 

Exhaust 

Cam 

37.05 

 

Replace with the new camshaft if the 
measured value exceeds the limit value.

 

 

4)  Examine diameter of valve stem 

a:  Measure the diameter of valve stem with 

micrometer caliper. 

See the picture for measuring points: they are 
26, 52, and 78 mm from measure positions to 
bottom of valve. 

 

 

Valve 

Guide 

External Diameter

Of Valve Stem 

Internal Diameter 

Of Valve Guide 

 

Measuring Point 

CHERY A21 SERVICE MANUAL

         

MECHANISM OF 2.0NALC ENGINE 

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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. 

 

 

 

Measuring Point 

Contact Position (Should be 

the Center of Slope) 

Edge 

Thickness

CHERY A21 SERVICE MANUAL

         

MECHANISM OF 2.0NALC ENGINE 

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Standard 

Value 

Outer Diameter 

of Valve stem 

(mm) 

IN 

￠5.98±0.008

EX 

￠5.96±0.008

Inner Diameter 

of Valve guide 

(mm) 

IN 

￠5.4±0.1 

EX 

￠5.4±0.1 

Clearance 

(mm) 

IN 

0.02 

EX 

0.04 

Thickness of 

Valve Top 

（mm） 

IN 

0.3±0.15 

EX 

0.3±0.15 

Seal Bandwidth 

（mm） 

IN 1.158 

EX 1.306