Buell 2002 P3 Service Manual page 178

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Replacing Valve Seats
Replacing a valve seat is a complex operation requiring spe-
cial equipment. If the seat is loose or is not fully seated in the
head, then seat movement will prevent the proper transfer of
heat from the valve. The seat surface must be flush with (or
below) the head surface. See
seat-to-cylinder head fit.
To remove the old seat, lay a bead of weld material around
the inside diameter of the seat. This will shrink the seat out-
side diameter and provide a surface for driving the seat out
the port side.
Lapping Valve Faces and Seats
NOTE
If valve faces and seats have been smoothly and accurately
refaced, very little lapping will be required to complete the
seating operation.
1. See Figure 3-60. Use CYLINDER HEAD HOLDING FIX-
TURE (Part No. HD-39786) to secure cylinder head.
a. Apply a light coat of fine lapping compound to valve
face. Insert valve in guide.
b. Place one rubber cup end of VALVE LAPPING
TOOL (Part No. HD-96550-36A) onto head of valve.
c. Holding lapping tool as shown, apply only very light
pressure against valve head.
d. Rotate lapping tool and valve alternately clockwise
and counterclockwise a few times.
2. Lift valve and rotate it about 1/3 of a turn clockwise.
Repeat lapping procedure in Step 1.
3. Repeat Step 2. Then, remove valve.
4. Wash valve face and seat. Dry parts with a new, clean
cloth or towel.
5. Inspect valve and seat.
a. If inspection shows an unbroken lapped finish of uni-
form width around both valve and seat, valve is well
seated.
b. If lapped finish is not complete, further lapping (or
grinding and lapping) is necessary.
3.1 SPECIFICATIONS for valve
5696
Figure 3-59. Measuring Valve Stem Protrusion
5693
Valve Lapping Tool
(HD-96550-36A)
Cylinder Head Holding Fixture
(HD-39786)
Figure 3-60. Lapping Valves
2002 Buell P3: Engine 3-31