Valves should only be lapped with fine grinding paste. For the necessary rotation, a rubber suction cup is installed on the valve disc. The formation of grooves can be avoided by frequently lifting and further uniform rotation of the valve during the lapping process in different directions.
Attention! After lapping, carefully remove the grinding paste. The lapping process can be checked by the type of work surface or by using fuel.
Insert the valve, fill the combustion chamber with gasoline, fuel must not flow out of the valve guide, otherwise repeat the lapping.