Yamaha WaveRunner FX Cruiser SHO, Service Manual

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POWR
• If the valve seat contact width is too narrow
and situated near the bottom edge of the
valve face, use a 60
° cutter to cut the bottom
edge of the valve seat, and then use a 45 °
cutter to center the area and set its width.
b
Previous contact width
60 ˚
b
6. After refacing the valve seat to the speci-
fied contact width, apply a thin, even layer
of lapping compound onto the valve seat,
and then lap the valve using a valve lapper
(commercially available).
CAUTION:
Do not get the lapping compound on the
valve stem and valve guide.
7. After every lapping procedure, be sure to
clean off any remaining lapping compound
from the cylinder head and the valves.
8. Check the valve seat contact area of the
valve again.
Refer to
“ Valve seat check. ”
NOTE:
After refacing the valve seat, check that the
valve clearance is within specification. Refer to
“ Valve clearance measurement ” in Chapter 3.
Cylinder head