CYLINDER HEAD/VALVE VALVE SEAT INSPECTION/ REFACING Clean all intake and exhaust valves thoroughly to remove carbon deposits. Apply a light coating of valve lapping compound to each valve face. Lap each valve and seat using a rubber hose or other hand-lapping tool. NOTE: Take care not to allow the compound to enter between the valve stem and guide. After lapping, wash out the compound completely and apply a coat of engine oil to the valve face and seat. SEAT WIDTH: 0.99-1.27 mm (0.039-0.050 in) Remove the valve and inspect the face. CAUTION: The valves cannot be ground. If the valve face is rough, worn unevenly, or contacts the seat improperly, the valve must he replaced. Inspect the valve seat. If the seat is too wide, too narrow, or has low spots, the seat must be ground. NOTE: Follow the refacer manufacturer's operating instructions. After cutting the seat, apply lapping compound to the valve face, and lap the valve using light pressure. After lapping, wash any residual compound off the cylinder head and valve. SERVICE LIMIT: 1.5 mm (0.06 in) IN: CUTTER (300) IN, EX: CUTTER (300) IN: CUTTER (290) EX: CUTTER (250) EX: CUTTER (24.50) OLD SEAT WIDTH 60° OLD SEAT WIDTH 0.99-1.27 mm (0.039-0.050 in) 148 Date of Issue: May, 1982 10 HONDA MOTOR CO., LTD. 10-14