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ENG
CYLINDER AND PISTON
EAS00265
CHECKING THE PISTON PIN
1. Check:
•
piston pin
Blue discoloration/grooves
→
Replace the
piston pin and then check the lubrication
system.
2. Measure:
•
piston pin outside diameter
a
Out of specification
→
Replace the piston
pin.
3. Measure:
•
piston pin bore diameter
b
(in the piston)
Out of specification
→
Replace the piston.
4. Calculate:
•
piston-pin-to-piston-pin-bore clearance
Out of specification
→
Replace the piston
pin and piston as a set.
Piston pin outside diameter
19.991 ~ 20.000 mm
(0.7870 ~ 0.7874 in)
<Limit>: 19.971 mm (0.7863 in)
Piston pin bore diameter
20.004 ~ 20.015 mm
(0.7876 ~ 0.7880 in)
<Limit>: 20.045 mm (0.7892 in)
Piston-pin-to-piston-pin-bore clearance =
Piston pin bore diameter
b
–
Piston pin outside diameter
a
Piston-pin-to-piston-pin-bore
clearance
0.004 ~ 0.024 mm
(0.0002 ~ 0.0009 in)
<Limit>: 0.074 mm (0.0029 in)
EAS00267
INSTALLING THE PISTON AND CYLINDER
1. Install:
•
top ring
•
2nd ring
•
lower oil ring rail
•
upper oil ring rail
•
oil ring expander
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