Yamaha F15A - Piston Pin Inspection; Piston Ring Inspection; Piston-To-Cylinder Clearance

E
CRANKCASE AND CRANKSHAFT
POWR
a
10 mm (0.4 in)
Piston-to-cylinder clearance
1. Calculate:
9 Piston-to-cylinder clearance
Out of specification → Replace the
piston and piston rings, the cylinder
or both.
Piston pin inspection
1. Measure:
9 Piston pin outside diameter
Out of specification → Replace the
piston pin.
Piston ring inspection
1. Measure:
9 End gap a
Out of specification → Replace the
piston ring.
NOTE:
Push the piston ring into the cylinder with
the piston crown.
5-39
Piston-to-cylinder clearance:
0.035 ~ 0.065 mm
(0.0014 ~ 0.0026 in)
Piston pin outside diameter:
13.996 ~ 14.000 mm
(0.551 ~ 0.5512 in)
Piston-to-
cylinder
clearance
Cylinder
bore
Piston
diameter
=
-
End gap (installed)
Top ring:
0.15 ~ 0.30 mm
(0.006 ~ 0.012 in)
2nd ring:
0.30 ~ 0.50 mm
(0.012 ~ 0.020 in)
Oil ring:
0.20 ~ 0.70 mm
(0.008 ~ 0.028 in)