POWR Power unit5-33 67C3K114. Determine the valve seat contact widtha by measuring the blueing dye markingon the valve face. Reface the valve seatif the valve is not seated properly or if thevalve seat contact width is out of specifi-cation. Check the valve guide if the valveseat contact width is uneven.Refacing the valve seat1. Reface the valve seat with valve seatcutters.2. Cut the surface of the valve seat with a45° cutter by turning the cutter clockwiseuntil the valve seat face has becomesmooth.a Slag or rough surfaceCAUTION:Do not over cut the valve seat. Be sure toturn the cutter evenly downward at a pres-sure of 40–50 N (4–5 kgf, 8.8–11 lbf) toprevent chatter marks.3. Use a 30° cutter to adjust the contactwidth of the top edge of the valve seat.Valve seat contact width a:Intake and exhaust:0.9–1.1 mm (0.035–0.043 in)S68V5720Valve seat cutter holder:90890-06316Valve seat cutter:30° (intake): 90890-0632730° (exhaust): 90890-0632845° (intake): 90890-0632545° (exhaust): 90890-0631260° (intake and exhaust):90890-06323S67C5090S6AG5J20J45˚a
