KAYO MOTOR A180, Service Manual

Page: 134 / 213

‐
4.Cylinder head/valve
Use a 45° cutter to grind the seat surface to the
specified width.
Trim again if necessary.
Apply a thin layer of Prussian blue or red lead on
the valve seat surface.
Install the valve through the guide tube until it is
in contact with the valve surface, lightly press the
valve, but do not rotate, so that a clear mark is
produced on the valve surface (the entire
circumference must be evenly contacted).
If the contact surface on the valve valve is too high,
grind the valve seat with a 32
°
cutter.
Confirm that all rough potholes and irregular
surfaces have been completely removed.
The position of the contact surface between
the valve seat and the valve is very important
for the tightness of the valve.
NOTE
NOTE
Width of old valve seat
Width of old
valve seat
The contact surface is too high