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1.2L REVOTRON ENGINE
65
I. Piston and Piston Rings :
1. Remove carbon deposits, if any, from the
piston.
2. Clean piston and piston rings using
appropriate cleansing agent.
NOTE
The piston and piston rings can be reused
if the bore taper and sphericity is within the
specified limits.
Carefully examine the piston rings for
cracks, scoring, ring groove/ clip groove
wear, piston pin bore wear.
In case anyone piston is found to have any
one of the above defects, replace the
complete piston set.
3. Check for lateral clearance in piston ring
groove.
4. Check for butt clearance in cylinder bore.
5. Check for piston pin dimensions.
NOTE
Butt clearance of piston ring is measured in
unworn portion of the cylinder bore.
Piston and piston rings of appropriate size
should be used, if cylinder bores are re-
bored.
If piston ring is found to be defective as
started above, then complete ring set
should be replaced.
Piston and Cylinder Bore Sizes (REVOTRON 1.2L)
Type
Grade
Cylinder Bore Dia. (mm)
Piston Dia. (mm)
Standard
A
77.015/77.025
76.950/76.960
B
77.025/77.035
76.960/76.970
Piston Rings (REVOTRON 1.2L)
Type of ring
Ring Thickness (mm)
Axial Clearance in
Piston Groove (mm)
Butt Clearance in
Cylinder Bore (mm)
1
st
Compression Ring
1.170/1.190
0.06/0.1
0.17/0.32
2
nd
Compression Ring
1.47/1.49
0.05/0.09
0.4/0.6
3
rd
Oil Control Ring
1.95/1.89
0.06/.014
0.2/0.7
Details
Specification
(mm)
Piston pin diameter
17.995/18.000
Piston pin length
46.7/47.0
Piston pin bore in piston
18.003/18.008
Height of piston
43.8
Piston to bore clearance
0.055/0.075