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1.5L REVOTORQ BS VI ENGINE
67
K. 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.
Details
Specification (mm)
Piston pin diameter
27
-0.005
Piston pin length
62
-0.3
Piston pin bore in piston
27.007-27.013
Height of piston
66.9
Piston to bore clearance
0.06 - 0.08
Maximum permissible
difference in weights in
each set for 4 pistons
5 gms
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 stated
above, then complete ring set should be
replaced.
Piston and Piston Dia. (mm)
Type
Grade
Piston Dia. (mm)
Cyl. Bore Dia. (mm)
Standard
A
75.930 - 75.939
76.000 ~ 76.009
B
75.940 - 75.949
76.010 ~ 76.019
C
75.950 - 75.960
76.020 ~ 76.030
Piston Rings
Type of ring
Ring Thickness (mm)
Axial Clearance in
Piston Groove (mm)
Butt Clearance in
Cylinder Bore (mm)
1
st
Compression Ring
1.73 / 1.75
0.01-0.03
0.2 to 0.3
2
nd
Compression Ring
1.47 / 1.49
0.05 - 0.09
0.35 to 0.50
3
rd
Oil Control Ring
1.97 / 1.99
0.03 - 0.07
0.2 to 0.4