Water leak under dash 1973 Eldorado

[bmyrheim]

When it rains my Eldorado has a water leak under the dash on the drivers side. I think it has something to do with the drainage from the windshield, as covering up the windshield and lower wiper area with tarp seems to stop the water spillage. I haven't removed the dashboard or anything yet, but looking under the dashboard I can see a rectangular box at the top which seems somewhat rusty. Has anyone had or looked into this problem before? And how does the drainage from the windshield works? I can see some drainage holes in the gutter under the wipers, but where does the drainage water suppose to go?

B.Myrheim

[V63]

In all probability it's a faulty windshield install. Verify its not an OEM windshield.

Maybe have someone inside the car with air pressure and follow perimeter at same location outside with soap bubbles?

Or

maybe pressurize the interior with industrial fan and spray soap bubbles around the exterior glass?

[TJ Hopland]

Water tends to follow wiring so the leak may not be were you think it is.    You could end up with the carpet pulled back and half the dash apart and still not see where its getting in. 

I have had some luck with painters tape making temporary 'seals' in specific areas trying to narrow down where its getting in.  If you put it on dry it sticks pretty good and doesn't seem to have a problem with water.  You can even use it to fill in big areas if there is one you suspect.