Chery S11 / Chery QQ. Manual — part 224

SQR7080 维修手册 372 发动机机械部分

4 Remove the main bush of the crankshaft, the
crankshaft, the crankshaft bush, and the axial thrust
plate of crankshaft
Check the radial clearance of the crankshaft
(1) Remove the crankshaft bearing cover; use a resin
hammer to knock the bearing cover off gently.
(2) Clean the inside of the bushes, the inside of the
bearing cover, the cylinder walls, the axle diameter,
etc. Make thorough checks for any tears and wears as
well as other damages.

(3) Use a clearance+6 gauge to adjust the radial
clearance of the crankshaft; tighten the bolts of
bearing bush cover with specified torque. [Torque]
70±3.5N.m

[Attention] Tighten the bolts of the crankshaft bearing
cover in three times to the regulated value, in the
sequence as shown in the right figure.
Attention: Don’t turn the crankshaft after
tightening ,because of the clearance gauge.

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SQR7080 维修手册 372 发动机机械部分

(4) Remove the bearing cover and measure the
maximum width of the spacing. If it goes beyond the
limit, replace the bush.
[Benchmark]:0.025-0.069mm
[Limit]:0.10mm

5 Disassembling of connecting rod assembly of the
piston

(1). Use the piston ring pliers to remove the primary
ring, the secondary ring and the oil ring
[Attention] Do not mix up the pistons and piston rings
for each unit of assembly.
(2). Use SST to remove the piston, connecting rod and
piston pin
①

Remove the piston pin to take off the piston and the

connecting rod by using SST.

7-3 Clearing
7-3-1 Cylinder body

Warning Wear eye glasses during the clearing

operation to protect your eyes.
1. Use flat chisel to clear the cylinder body, the
cylinder cover, the oil bottom casing, the oil pump and
the oil seal.

7-3-2 Piston

Waring Wear eye glassed in the process of cleaning to

protect your eyes.
1. Use the old ring to clean the accumulated carbon in
the ring groove.
2. Clean the accumulated carbon at various parts with
detergents.
[Attention] Do not use metal brush or some other hard
sutstance to do the cleaning.

Mark

SST

SST

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SQR7080 维修手册 372 发动机机械部分

7-4 Routine checks
7-4-1 Cylinder block
1. Checks on the levelness of cylinder top surface
(1). Use a ruler and feeler to do the measurements of
the six parts as shown in the right figure.
[Limit] 0.08mm
2. The use of cylinder meter: Measure the values at the
parts as shown in the right figure and work out the
maximum value and the minimum value. Replace the
cylinder body or do the boring of the cylinder if the
values exceed the limits.
[Limit] 0.03mm

[ Reference] Circularity：A-B or a-b
Cylindricity：A-a or B-b
[Reference] Cylinder standard diameter:

φ72.00-72.01mm

Bottom dead
center

Top dead
center

7-4-2 Piston

1. Check the clearance between the piston pinholes.
(1) Use a caliper to measure the positions of the piston shown in the following figure, with the
maximum value as the size of the piston pin diameter.

(2) Use the inner diameter centi-meter to measure the positions of the piston hole diameter shown as
the following figure, take the minimum value as the size of the pinhole diameter.

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SQR7080 维修手册 372 发动机机械部分

(3) Work out the clearance on the basis of the size difference between the hole diameter and the

pin diameter. Replace the piston pin or the piston if the result exceeds the benchmark value.

[Benchmark] 0.004-0.009mm
[Limit] 0.015mm

1. Measurement of the piston diameter
(1) Make the measurement at the position 11mm
below the piston skirt and along the vertical direction
of the piston pin.
[Benchmark]

φ72

–0.013

–0.025

2. Check the clearance between the piston ring and
the ring groove
(1) Use a feeler to measure the rings

Benchmark

(mm)

Limit (mm)

Primary ring

0.03~0.06

0.12

Secondary

ring

0.03~0.06 0.11

3. Check the clearance of piston ring ends

(1) Put the piston ring in the position which is 45

mm under the cylinder hole top surface,in order to
make the piston ring keep flattened,you can press the
piston ring with piston top surface,then use a piston
gauge to measure the open clearance.

Benchmark

(mm)

Limit (mm)

Primary ring

0.25-0.40

0.65

Secondary

ring

0.35~0.50 0.65

Oil ring

0.20~0.70

1.00

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