Additional valve grinding (VW Golf 1)

The reasons for unsatisfactory compression pressure may be worn pistons, piston rings and cylinders, as well as leaky valves. If the valves are still in good condition, it is enough to do additional grinding. Defective valves should be replaced, and new ones should be additionally ground. To do this work, you will need a special lapping paste for valves and a grinding device.

Remove the valves.

Lubricate the valve sealing surface with grinding paste, insert the valve back into the cylinder head. Under no circumstances should the paste get into the valve guide!

Place the device on the valve plate and rotate until a matte-shiny belt forms on the sealing surface.

The width of the belt should be 2.0 mm at the inlet valve and 2.4 mm at the outlet valve.

(The original information is posted on the resource vwmanual)

The finished, polished valve should be thoroughly cleaned of any remaining grinding paste and reinserted into its guide.