Orion AGB-21G - Checking the Piston Pin

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CYLINDER AND PISTON
NOTE:
NOTE:
2. Install:
piston ring
(into the cylinder)
Level the piston ring in the cylinder with the pis-
ton crown as shown.
a
5.0 mm
3. Measure:
piston ring end gap
Out of specification
Replace the piston
ring.
The oil ring expander spacer’s end gap cannot
be measured. If the oil ring rail’s gap is exces-
sive, replace all three piston rings.
Piston ring end gap
Top ring
0.10
0.25 mm
<Limit>: 0.60 mm
2nd ring
0.15
0.30 mm
<Limit>: 0.60 mm
Oil ring
0.2
0.5 mm
CHECKING THE PISTON PIN
1. Check:
piston pin
Blue discoloration/grooves
Replace the
piston pin and then check the lubrication sys-
tem.
2. Measure:
piston pin outside diameter
a
Out of specification Replace the piston
pin.
Piston pin outside diameter
13.994
14.000 mm
3. Calculate:
piston-pin-to-piston clearance
Out of specification Replace the piston pin
and piston as a set.