Like Dan said.
I don't have a Mercedes, but there is only a single
zinc on my engine
, and its on the raw water heat exchanger
. It is a "pencil" zinc the screw into a brass plug
that screws into the side of the heat exchanger
. Look for a large brass bolt head
that kind of looks like it would be a drain plug
. May be the zinc will be totally gone, and only the brass plug is still there. Check the pencil zincs at the marine hardware
as they are sold both with and without the brass plug, and you will know what to look for.
If engine is raw water
cooled, then the above will make no sense.