Chery Fora (Elara A520). Manual — part 137

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7)

Use wood stem to uplift the connecting
rod and piston slightly, and then
dismantle the piston and connecting rod
assembly.

8)

Take down the piston ring.

9)

Take down the retainer ring of piston
pin, and pull out the piston pin.

Note: Since the tension force of retainer ring
is very strong, you should do the removal
work carefully in order to avoid hurting
person.

3.2.2 Inspection

I.

Check the piston

1) Check the piston diameter.

Use micrometer caliper to carry out
measurement at the position 11mm away
from the lower part of piston skirt section a
and along the vertical direction of piston pin.

Cylinder

No.

Standard

Size

Wearing

Limit

1

80.46±0.009

2

80.46±0.009

3

80.46±0.009

4

80.46±0.009

Please replace the piston when it exceeds the
wearing limit.

Locating Snap Ring

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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.

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.