Chery Fora (Elara A520). Manual — part 46

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2)

Check the clearance between piston ring
and ring slot.

a.

Use piston ring to clean up the carbon
deposit in the ring slot.

b.

Use feeler gauge to measure the
clearance between the piston ring and
ring slot.

Standard

value(mm)

Wearing limit

(mm)

First

ring

0.04--0.08

Second

ring

0.01--0.025

If the measured clearance exceeds wearing
limit, please replace it with new piston.

3)

Check the end clearance of piston ring

a.

Put the piston ring at the position 45mm
below the top surface of cylinder
aperture, and push the piston ring into
cylinder with piston.

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b. Use feeler gauge to measure the orifice.

If the measured clearance value exceeds the
limit, please Replace with a new piston ring.

Standard value

(mm)

Limit (mm)

First

ring

0.2-0.4

Second

ring

0.4-0.6

Oil

ring

0.2-0.9

4)

Check the piston pin and the diameter of piston pin

a.

Use micrometer caliper to measure the outer edges of the part shown in the following
figure, and select the maximum value as the diameter size of piston pin.

b.

Use inner micrometer caliper to measure the outer edges of the parts of the piston pin
hole shown in the following figure, and select the minimum value as the diameter size of
piston pin hole.

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Standard size

Wearing limit

Clearance between piston pin and piston pin hole

0.002-0.013

5)

Check the connecting rod journal and
the connecting rod bearing.

a.

Check the diameter of connecting rod
journal.

Use micrometer caliper to measure the
connecting rod journal.

Rotate the crankshaft for 90°, and carry out
measurement.

Calculate the roundness and cylindericity
after two measurements.

Standard

value

Wearing

limit

Diameter

Roundness

Cylindericity

b.

Check the radial clearance of connecting
rod bearing.

Use clearance gauge to measure the radial
clearance of connecting rod bearing. Firstly
clean the connecting rod journal and
connecting rod bearing, and then put the
clearance gauge onto the journal, and fasten
the bearing bush to specified torque.

Note: The crankshaft should not be rotated
during this process.

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Loosen the connecting rod bolt, dismantle the
bearing cap; and use the measuring rule on
the clearance gauge packaging bag to
measure the width of the widest portion of
the flattened clearance gauge, and get the
clearance value.

If the measured clearance exceeds limit, you
should replace the connecting rod bearing.

Note: When replacing bearing bushing, you
should use the specified brand and model of
the same manufacturer.

Standard value

Wearing

limit

clearance

0.15

0.50

6)

Check the flatness of the cylinder block
surface.

a:

Clean the cylinder block surface.

b:

Use ruler and feeler gauge to check
whether the cylinder block surface is
warped or not.

C:

If the warping amount is excessive,
please rectify it.

If it exceeds the limit, please replace the
cylinder block.

The maximum summation of the permitted
worn thickness of the cylinder block and
cylinder head is:

Standard value

Limit
value

warping

amount

0.04

Plastic Gauge