Yes, I just had that problem on my 89 420SEL ... the rubber grommets that fit into the washer pump holes disintegrated. You can get those from Phil or the MB dealer and insert them, putting the pump down through them into the tank. The second hole is for the headlight washer system that is on 420's and other models of that era and of course a second grommet and pump goes into that area.

__________________
Ben Harrison Carter
1999 Mercedes ML320 87K
1992 Mercedes 300CE 89K
1995 Corvette 29K -- Sold Dec 09
1989 Mercedes 420SEL 99K -- (Sold 4/08)
1968 Mercedes 230S (106K) (Sold 9/06))
1976 Mercedes 450SEL 130K (Just sold - 06)
1961 Mercedes 220Sb (sold years ago)