There is a drain hole around there - I'm pretty sure there is - been some time since I was last poking around my W123 though.

If you remove the plastic covers behind the rear wheel in the arch you might be able to see a better view of what the structure looks like. If there's evidence of a lipped / pressed recess then it is meant to be there (and probably a rubber drain like bung too)...

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!