Mercedes-Benz 201.024 Service Manual page 256

Note
The valve seat rings are sintered metal on
account of lead free fuel.
These hardened valve seat rings temporarily had
a step (arrow) on the inside of the ring.
This step must be turned off in order to machine
the valve seat ring. There is a repair valve seat
ring with larger outside diameter as a replace-
ment part for all valve seat ring designs. After
renewing valve seat rings, the fitting condition of
the hydraulic valve clearance compensating
elements must be checked and corrected if
necessary (05214).
05.0906 - 29014
Intake
EXIT
PO5 -0164 -11