Checking The Piston Ring Grooves; Checking The Piston Ring Side Clearance - Yamaha F15B Service Manual

2. Level the piston ring 1 in the cylinder
with a piston crown.
3. Check the piston ring end gap d at the
specified measuring point. Replace if out
of specification.
e
Piston ring end gap d:
Top ring:
0.15–0.30 mm
(0.0059–0.0118 in)
Second ring:
0.30–0.50 mm
(0.0118–0.0197 in)
Oil ring:
0.20–0.70 mm
(0.0079–0.0276 in)
Measuring point e: 10 mm (0.4 in)
6D45F11
1
d
6D451210

Checking the piston ring grooves

1. Measure the piston
Replace the piston if out of specification.
Piston ring groove:
Top ring a:
1.23–1.25 mm
(0.048–0.049 in)
Second ring b:
1.52–1.54 mm
(0.0598–0.0601 in)
Oil ring c:
2.51–2.53 mm
(0.099–0.100 in)
Checking the piston ring side
clearance
1. Measure the piston ring side clearance.
Replace the piston and piston rings as a
set if out of specification.
Cylinder block
ring grooves.
1
2
3
6D451220
4
5
6
7
a
8
b
9
c
6D451230
5-40