W126 water in trunk - PeachParts Mercedes-Benz Forum

bschwar · #1 11-08-2005, 04:45 PM

Hi all, I'm trying to figure out where the water is coming from in the left (drivers) side trunk well of my 84 300SD. I've got a minor case of the rear glass delaminating, so that is a suspect. Before I spring for new glass, I'd like to cover my bases. There is some form of a drain in the well, but the top of it is not connected to anything. Where is this supposed to go? Is it a water drain? I was wondering if it could be the sunroof drain. If so, that could explain things.
Barry

donbryce · #2 11-08-2005, 05:47 PM

'85 380SE, same problem. I get water in both wells, left and right of spare tire well. I've ruled out the trunk weatherstrip, as I can't see any penetration anywhere.
I ran a good bead of silicone under the sides and bottom rubber flanges of the rear window seal too, thinking it was seeping in somewhere around the sides/bottom of the glass (BTW, glass was replaced last year, bad delamination both corners, but they re-used the old rubber seal. The new glass wasn't OEM and a bit thinner I thought, so may not have sealed properly) Didn't help.
There's a water drain hole in the bottom of both wells in my model. The left one accomodates the drain tube from the power antenna, which the lack of, or positioning of, may be your problem, especially if you have a non-original power antenna that either lacks this tube or fits poorly at the fender grommet.
I believe my sunroof drains exit at the rear of the rear wheel wells, outside the trunk, so are not suspect. All I can think of now is to get inside the trunk and have my son spray the area liberally with the garden hose. Maybe I can see where it's coming from if the carpet liners are out....but that may not happen until spring. Hope my comments help.

andmoon · #3 11-08-2005, 07:01 PM

Mine were leaking from the rear lights. A hose to the lights while looking in might show the leak. There are 2 hgaskets per side involved. 1 is between the light assembly and body. 2 is the red white and yellow portion of the light and the black body of the assembly.

raymr · #4 11-08-2005, 10:35 PM

Mine was leaking heavily from the forward area below the rear window. I sealed the ENTIRE back window glass-to-rubber union with black marine sealant. Also sealed the top and sides where the rubber contacts the body with the same material. No leaks since. Prep is very important, as a lot of gunk settles in there which will make the sealant not work. Several hours of cleaning with rags, alcohol, and popsicle sticks is required.

Hatterasguy · #5 11-08-2005, 10:36 PM

If you are getting water on the drivers side replace this seal:
http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1MB12FET61NN1CBMXU&year=1987&make=MB&model=300-SDL-001&category=Z&part=Antenna+Seal

It costs nothing takes a few minutes and is usually the suspect.

Water can also come in from behind your tail lights.

Now water should not come in from the rear glass regardless of the glass or its seals condition. Their is a metal lip under the glass that will not let water into the trunk, unless it is rusted through. So if you are getting water in your trunk from the rear glass you have a hidden rust problem. I sudjest pulling the glass and dealing with it if you plan on keeping the car.

PaulH · #6 11-08-2005, 10:49 PM

A friend of mine replaced the rear window seal on his '85 300 SD and that stopped the leak in his trunk.

Hatterasguy · #7 11-08-2005, 10:53 PM

It shouldn't have their is just plain sheet metal under the seal. However in each corner their is a hole that the factory made for some reason when they were building the cars. They are usually filled with paint and body filler, it is possible that one could have come un plugged.

raymr · #8 11-08-2005, 10:58 PM

Quote:

Originally Posted by Hatterasguy

Now water should not come in from the rear glass regardless of the glass or its seals condition. Their is a metal lip under the glass that will not let water into the trunk, unless it is rusted through. So if you are getting water in your trunk from the rear glass you have a hidden rust problem. I sudjest pulling the glass and dealing with it if you plan on keeping the car.

This is my problem, as water was coming down thru what looks like 2 spotwelded pieces. The prices I got to replace the glass and seal were very high (over $1000), not counting fixing the damage underneath. Sad to say I can't justify the expense. I'm hoping that by stopping the leak, the rust won't progress, or else progress very slowly.

bschwar · #9 11-09-2005, 08:34 AM

I do have an aftermarket antenna, so that explains where that drain was supposed to go. I did get the original antenna handed to me when I bought the car, but I didn't see where the drain would connect to it. I may try putting that back with a new mast and new seal.

I hadn't looked at the tail lights because the water seems to be comming from the front. I may take a closer look, though, because as the saying goes, things are not always as they seem.

I did also have water in the right (passenger) side wheel well. I think I pinned that down to a cracked bellows seal around the fuel fill, and a leaking fuel fill overflow drain tube. Time will tell if I really fixed the water on that side.

As for the rear window, I guess it would be worth it to try sealing it first. How do I go about removing the trim without damaging it, and how tough is it to do?

Thanks again for all the advice
Barry

spisfam · #10 03-13-2006, 10:43 AM

I am suffering the same fate with my 85 380se water in the drivers side trunk tire well, I have replaced the rear windshield with new rubber and that is a job and a half, and if you need the glass go to your search engine and look up Pilkington glass classic, there is a 1 800 number in Columbus, mine was two fifty or just over with a hundred dollar delivery so I bought some glass for my volvo. The guy there is called AL, he has all the makes numbers. As for the leak it is still there, out of curiosity I am going to remove the crome trim on the water drain that is over the doors running from front to rear, if you open the doors you can see the screws that retain it, I even sealed up my sun roof and it still came through, and when I sealed around the rear windshield no different, the crome trim is my only other option.
I hope this is of some help to you all.

86560SEL · #11 03-13-2006, 07:30 PM

Well, to update on my car (85' 380SE) the new antenna seal. I never knew how much water was in there, but I know it was damp and as you can see in the above photo, the seal was tattered. I had water in my right rear floor panel. Ironically, when I replaced this seal, water stopped coming in the right rear floor. Strange, but somehow the water was flowing over there.

I still have a little bit of water coming from one taillamp, which I will tend to soon.