Valve seat machining (VW Beetle)

Valve seats with slight wear or burn marks can be machined, but only as long as the 15-degree milled chamfer on the outer perimeter of the seat ring outer diameter is maintained. Otherwise, the cylinder head needs to be replaced. During processing, cutters with appropriate geometry are used.



The 45° chamfer must be machined with particular care to ensure proper seat alignment. To prevent the cylinder head from wearing out prematurely, the material must be removed until it begins to be removed across the entire width of the working chamfer.



The lower edge at 75° angle of the exhaust valve seat ring surface should be slightly bent at this angle.



The top edge with a 15° angle of the seat ring surface must be cut at this angle until the correct width "a" of the working chamfer is achieved.





(The original text can be found on the portal: «VWMANUAL.ru»)

The width "a" of the working chamfer should be 1.4-2.5 mm.