Cylinder And Piston Inspection - Yamaha WaveRunner FX140 Service Manual

POWR
a
b
D
2
c
D
4
D
6
CONNECTING RODS AND PISTONS
D
1
d
D
3
e
D
5
3. Remove:
• Top ring
• 2nd ring
• Oil ring
NOTE:
When removing a piston ring, open the end
gap with your fingers and lift the other side of
the ring over the piston crown.

Cylinder and piston inspection

The following procedure applies to all of the
cylinders and pistons.
1. Check:
• Piston wall
• Cylinder wall
Vertical scratches → Replace the cylin-
der, and the piston and piston rings as a
set.
2. Measure:
• Piston-to-cylinder clearance
Measurement steps:
• Measure cylinder bore "C" with the cylin-
der bore gauge.
NOTE:
Measure cylinder bore "C" by taking side-to-
side and front-to-back measurements of the
cylinder. Then, find the average of the mea-
surements.
Cylinder bore "C"
Taper limit "T"
Out of round "R"
"C" = maximum of D
"T" = maximum of D
(direction e)
and D –D
2 6
"R" = maximum of D
point a) and D
5-87
74.060–74.075 mm
(2.9157–2.9163 in)
0.08 mm (0.003 in)
0.05 mm (0.002 in)
–D
1 6
(direction d)
–D
1 5
–D (measuring
2 1
(measuring point c)
–D
6 5
E