Yamaha WaveRunner FZR-GX1800 Service Manual page 182

POWR
30˚
30˚
30˚
b
Cylinder head
b
b
60˚
b
c
45˚
b
60˚
2. Use a 30° cutter to adjust the contact width
of the top edge of the valve seat.
b Previous contact width
3. Use a 60° cutter to adjust the contact width
of the bottom edge of the valve seat.
b Previous contact width
4. Use a 45° cutter to adjust the contact width
of the valve seat to specification.
b Previous contact width
c Specified contact width
5. Check the valve seat contact area of the
valve.
Refer to "Valve seat check."
Example:
• If the valve seat contact width is too wide and
situated in the center of the valve face, use a
30° cutter to cut the top edge of the valve
seat, and then use a 60° cutter to cut the bot-
tom edge to center the area and set its width.
b Previous contact width
• If the valve seat contact width is too narrow
and situated near the top edge of the valve
face, use a 30° cutter to cut the top edge of
the valve seat, and then use a 45° cutter to
center the area and set its width.
b Previous contact width
5-75
E
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