Chery T21 2014 Service Manual page 509

Roundness error is half of the diameter difference measured at the same section.
Roundness of Section A = (maximum bore diameter measured in thrust direction and axial direction at
point A - minimum bore diameter measured in thrust direction and axial direction at point A)/2
Roundness of Section B = (maximum bore diameter measured in thrust direction and axial direction at
point B - minimum bore diameter measured in thrust direction and axial direction at point B)/2
Roundness of Section C = (maximum bore diameter measured in thrust direction and axial direction at
point C - minimum bore diameter measured in thrust direction and axial direction at point B)/2
Compare maximum value roundness measured at A, B and C with the standard cylinder roundness.
b. Check cylindricity of cylinder.
Using a cylinder gauge, measure the cylinder bore at
positions A, B and C in the thrust and axial directions.
Measurement Item
Cylinder Cylindricity
Cylinder Roundness
If the cylindricity or roundness value measured at
positions A, B and C exceeds the specified value,
replace the engine block.
4. Check piston.
a. Using a scraper, remove the carbon deposits on the
top of piston.
b. Using a piston ring, remove the carbon deposits in the
piston ring groove.
Chery Automobile Co., Ltd.
Specification
(mm)
0.01
0.008
Axial Direction
07 - SQR484F ENGINE MECHANICAL
Thrust Direction
Front
A
12 mm
B
Center
C
12 mm
07
RT21071040
RT21071050
RT21071060
87
07–