Fig. 15—Installing Cylinder Sleeve
e. Valve Seat Refacing. Reface each valve seat with a 90
degree (included angle) valve seat grinding wheel or valve seat
cutter until the face of the seat is "cleaned up" and free from pits
or nicks. If a valve seat cutter is used, it will be necessary to lap the
valves into the seat. The time ordinarily required to lap the valves
is saved by using an eccentric type valve seat grinder with which
the grinding wheel contacts only one portion of the seat at any
given time. If the grinder, including the pilot, is in good condition
and the grinding wheel is kept sharp and properly dressed, it ordin-
arily is not necessary to lap the valves into the seats. After refacing,
the width of the valve seat should not be more than 0.125 inch,
measured across the face of the seat (fig. 16). If the seat is too wide,
remove just enough stock from the top and/or bottom of the seat
to reduce the width to 0.062 inch. Use a 120 degree (included angle)
valve seat cutter for removing stock from the top of the seat and a
60 degree (included angle) cutter for removing stock from the
bottom of the seat.
§ 122. e.
3695-47
20
Sleeve Replacer
SLEEVE
RM-636