W123 Water in Driver's Side Rear Floor - Page 2 - PeachParts Mercedes-Benz Forum

t walgamuth · #16 09-25-2021, 01:07 PM

take a weed eater string and push out in the corner of the sunroof until you find the drain, then push it down til you can see it coming out the drain which is in the wheel well.

The main culprit in my mind is the windshield rubber.

RML · #17 09-25-2021, 04:52 PM

I pushed the weed eater line through on both sides of the front of the sun roof and it came through below very easily through a small hole in the door jamb. Are there drain holes at the rear of the sunroof as well which drain to the rear?

I examined the front windshield rubber gasket quite thoroughly. It does not appear compromised. However, where the gasket meets the roof, that is just an overlap and not a water tight seal. It appears that the design is for any water getting under there travels down to the outlet in the wheel well. I ran water under the overlapping rubber gasket and could see it coming out at the wheel well. So, I do not think anything in there is blocked.

I am thinking that I may need to run a lot of water over different locations and observe the rear floor to narrow down the source of the problem.

t walgamuth · #18 09-25-2021, 05:24 PM

There is a drain at each corner of the sunroof gutter.

t walgamuth · #19 09-25-2021, 05:26 PM

The windshield glass and gasket can be cleaned out with a plastic knife or such. cleaned and caulked with black silicone. It is not as clean as installing a new gasket but it is a lot less money.

Usually on an older car the windshield is pitted. A new glass and gasket is around 250.

t walgamuth · #20 09-25-2021, 11:35 PM

Quote:

Originally Posted by RML

I pushed the weed eater line through on both sides of the front of the sun roof and it came through below very easily through a small hole in the door jamb. Are there drain holes at the rear of the sunroof as well which drain to the rear?

I examined the front windshield rubber gasket quite thoroughly. It does not appear compromised. However, where the gasket meets the roof, that is just an overlap and not a water tight seal. It appears that the design is for any water getting under there travels down to the outlet in the wheel well. I ran water under the overlapping rubber gasket and could see it coming out at the wheel well. So, I do not think anything in there is blocked.

I am thinking that I may need to run a lot of water over different locations and observe the rear floor to narrow down the source of the problem.

There are drains in all four corners of the sunroof pan. If you only cleared them in front you may get water from the rear ones.

I used to clean the joint and caulk with black silicone caulk. Getting a new windshield and gasket is a good way to take dare of the gaskets and you get a new windshield as a bonus.