Figure 3-2. Removing valve guide.

Figure 3-2. Removing valve guide.

Figure 3-3. Locating valve guide depth.

d. Exhaust Valve Seat Replacement.

not less than 20 minutes, quickly drive seat into

(1) Using a valve seat puller, remove exhaust

counterbore with seat driving tool. If special tool is not

valve seat inserts (13, fig. 3-1). Take care not to

available, tap seat into place.

(5) Grind exhaust valve seat to a 45angle.

damage the seat counterbore.

(2) Clean all carbon from the seat counterbore

(6) All valves having less than 50 percent margin

and valve port.

thickness at outer edge of valve seat after refacing must

(3) Machine the counterbore to receive a seat

be replaced. Compare refaced valve with a new one to

0.010 inch larger diameter than the seat removed, to a

determine if thickness is less than 50 percent.

0.003-0.005 inch press fit.

(4) After chilling the new seat in dry ice for

3-3