Orion AGB-21G - Checking the Piston Rings

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CYLINDER AND PISTON
NOTE:
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.
1
7.0 mm from the bottom edge of the piston.
Piston size “P”
Standard 53.965 53.975 mm
d. If out of specification, replace the piston and
piston rings as a set.
e. Calculate the piston-to-cylinder clearance
with the following formula.
Piston-to-cylinder clearance =
Cylinder bore “C” –
Piston skirt diameter “P”
Piston-to-cylinder clearance
0.025
0.05 mm
f. If out of specification, rebore or replace the
cylinder, and replace the piston and piston
rings as a set.
CHECKING THE PISTON RINGS
1. Measure:
piston ring side clearance
Out of specification
Replace the piston
and piston rings as a set.
Before measuring the piston ring side clear-
ance, eliminate any carbon deposits from the
piston ring grooves and piston rings.
Piston ring side clearance
Top ring
0.04
0.08 mm
<Limit>: 0.12mm
2nd ring
0.04
0.08 mm
<Limit>: 0.12mm