Checking the valve guides (Audi A6 C4)

When repairing engines with leaky valves, it is not enough to simply rework or replace the valves. In addition, the valve guides should be checked for wear immediately. This check is especially important for engines with a long service life. If the wear is too great, the valve guides must either be replaced or (only in the workshop), or replace the cylinder head.

Remove carbon deposits on the valve guides using a cleaning reamer.

Insert the new valve. The end of the valve stem should not protrude from the guide.

Warning: Due to the different stem diameters, use intake valves only in intake guides and exhaust valves only in exhaust guides.

Use a linear travel indicator to measure the amount of travel the valve disc takes as it swings.

Wear limit: intake valve guide – 1.0 mm, exhaust valve guide – 1.3 mm.

If the travel value is greater, have the valve guides replaced by a workshop.