Valve Seat Reconditioning - Honda 2004 Odyssey Service Manual

Valve Seat Reconditioning

1. Inspect valve stem-to-guide clearance (see page 6-
48). If the valve guides are worn, replace them (see
page 6-49) before cutting the valve seats.
2. Renew the valve seats in the cylinder head using a
valve seat cutter.
3. Carefully cut a 45° seat, removing only enough
material to ensure a smooth and concentric seat.
4. Bevel the upper and lower edges at the angles
shown in the illustration.
Check the width of the seat and adjust accordingly.
1999-2001 models:
2002-2004 models:
30°
45°
60°
30°
45°
67.5° (intake seat)
60° (exhaust seat)
5. Make one more very light pass with the 45° cutter
to remove any possible burrs caused by the other
cutters.
Valve Seat Width
Standard (New): 1.25 1.55 mm (0.049 0.061 in.)
Service Limit: 2.00 mm (0.079 in.)
6. After resurfacing the seat, inspect for even valve
seating. Apply Prussian Blue compound (A) to the
valve face. Insert the valve in its original location in
the head, then lift it and snap it closed against the
seat several times.
B
A
7. The actual valve seating surface (B), as shown by
the blue compound, should be centered on the seat.
• If it is too high (closer to the valve stem), you
must make a second cut with the 60° cutter (1999-
2001 models and 2002-2004 models exhaust
side) or the 67.5° cutter (2002-2004 models intake
side) to move it down, then one more cut with the
45° cutter to restore seat width.
• If it is too low (close to the valve edge), you must
make a second cut with the 30° cutter to move it
up, then make one more cut with the 45° cutter to
restore seat width.
NOTE: The final cut should always be made with
the 45° cutter.
(cont'd)
6-51