I've had several W123's and they all had about half inch water in the floor pan after heavy rain, usually on the passenger side.
The drainage system off the roof seems to flow into a pocket around the bonnet hinge, where the lowest point has no drainage hole except the bonnet latch cable, which channels the water very effectively into the interior. What were the designers thinking?
I was thinking of filling that useless pocket with polyurethane foam and making a drainage tube coming from the window gutter.
What about all the other millions of 123's out there, what do they do?
-VARIS