Mercedes Benz repair: fuel, self priming, diesel filter

Question
i have just changed the diesel filter on my 1993 mercedes since doing this i have an air lock. how do i rectify this please

Answer
Try removing the filter, fill with fresh transmission fluid, and reinstall it.

You should not need to do this on a 1993 = it is a self-priming system = roughly twenty - thirty seconds of cranking should have it running again.
Is it possible the filter is not tight, or a line cracked during the filter change?