Lapping valves (VAZ-21099)

To check the tightness of the valve, install it in the head with springs and crackers. Then lay the head on its side and pour kerosene into the channel that is closed by the valve. If kerosene does not leak into the combustion chamber within three minutes, the valve is tight.



1. Apply a thin layer of lapping paste to the working chamfer of the valve.



2. Insert the valve into the guide bushing and attach the valve lapping tool to its stem.



3. Turn the valve vigorously in both directions using the tool, periodically pressing the valve against the seat.





4. An external sign of satisfactory lapping is a uniform matte-gray color of the valve working chamfer and seat. After lapping, carefully wipe the valve and seat with a clean cloth and rinse to remove any remaining lapping paste. Do not reuse the cloth.