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ENG
CYLINDERS AND PISTONS
EAS00258
CHECKING THE CYLINDERS AND
PISTONS
The following procedure applies to all of the
cylinders and pistons.
1. Check:
• piston wall
• cylinder wall
Vertical scratches
→
Replace the cylinder,
and the piston and piston rings as a set.
2. Measure:
• piston-to-cylinder clearance
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a. Measure cylinder bore “C” with the cylinder
bore gauge.
NOTE:
_
Measure cylinder bore “C” by taking side-to-
side and front-to-back measurements of the
cylinder. Then, find the average of the mea-
surements.
b. If out of specification, replace the cylinder,
and the piston and piston rings as a set.
c. Measure piston skirt diameter “P” with the
micrometer.
a
5 mm (0.20 in) from the bottom edge of the pis-
ton
Cylinder bore gauge
(50 ~ 100 mm)
YU-03017
Cylinder bore “C”
97.000 ~ 97.010 mm
(3.8189 ~ 3.8193 in)
Taper limit “T”
0.05 mm (0.0016 in)
Out of round “R”
0.05 mm (0.0016 in)
“C” = maximum of D
1
~ D
6
“T” = maximum of D
1
or D
2
- maximum of
D
5
or D
6
“R” = maximum of D
1
, D
3
or D
5
- minimum
of D
2
, D
4
or D
6
Micrometer (75 ~ 100 mm)
YU-03009