3-38 ENGINE • If the valve seat is pitted or burned, use the 45° cutter to con- dition the seat some more. NOTE: Cut only the minimum amount necessary from the seat to pre- vent the possibility of the valve stem becoming too close to the camshaft. TOP NARROWING CUT • If the contact area W is too high on the valve, or if it is too wide, use the 15° (for the exhaust side) and the 30° (for the intake side) to lower and narrow the contact area. E PL M 15˚ SA 30˚ BOTTOM NARROWING CUT • If the contact area W is too wide or too low, use the 60° cutter to narrow and raise the contact area. 60˚