CYLINDER AND PISTON
ENG
EAS00255
CHECKING THE CYLINDER AND PISTON
1. Check:
•
piston wall
•
cylinder wall
Vertical scratches
-*
Rebore or replace
the cylinder, and replace the piston and
piston rings as a set.
2. Measure:
piston-to-cylinder clearance
• • • • • • • • • • • • • • • • • • • • • • •
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 measurements.
Cylinder bore “C”
Taper limit “T”
Out-of-round “R”
“C” = maximum of D
38.000 ~ 38.010mm
(1.4961 ~ 1.4965in)
0.05mm (0.0020in)
0.05mm (0.0020in)
~ D
“T” = maximum of D or D
“R” = maximum of D
1
, D
3
or D
6
- maximum of D or D
or D
5
- minimum of D
2
, D
4
b. If out of specification, rebore or replace the
cylinder, and replace the piston and piston
rings as a set.
c. Measure piston skirt diameter “P” with the
micrometer.
a 5mm(0.1969in) from the bottom edge of the
piston
Piston size “P”
Standard
37.975 ~ 37.990mm
(1.4951 ~ 1.4957in)
d. If out of specification, replace the piston and
piston rings as a set.
5-33
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