Pull away carpet to expose the antenna. You will see one little philips head screw at the bottom. Remove the screw. Pull antenna down this may require a litte force. Don't pull to far or you will snap the ground! Unscrew the ground and the radio wire if you feel you need to. Push the old seal out. Soap/heat up the new seal if needed and push it in.


Replace the tailight gasket as well, then dry the trunk out and search for further leaks.

If you can see the rust outside the gasket their is probably a lot more under it. Pull the rear window, fix the rust and install a new gasket.

If the car is a beater, scrap and paint as best you can and shoot some silicone around the window.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Thanks. Well, it is a old car and I do not want to spend too much money on it.

Here are some photos I took of the mentioned areas.

I do not even think the antenna motor works, but I do not care - I just want to stop the leaks.

Appears to be a cut wire by that trunk hinge - it actually runs out of the hinge, but everything save for the antenna works. ????

You can see the moisture inside my trunk and that rust spot by the rear window. My window has some hazing there, but I have seen them much worse.

Attached Thumbnails

         

If you pull the rear window yourself you are probably looking at $150 max for seal, sealent, paint, sandpaper ect.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

What may help to find the leak is to tape a layer of newspaper in the trunk. Then spray the car with a hose or drive trough the rain and check where the paper gets wet. That should give you an idea where it is coming from.

Good idea.

I am wondering, are the W126 the only ones with these leak problems or do they plague other Mercedes as well? I have never heard of anyone with a W123 of the same vintage complaining of a trunk leak.

W123's leak just as much.

It age, these cars are getting old and all the seals are drying out. The newest W126 is now 15 years old.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I see.

My 69' Chevrolet has a leaky FRONT glass, as well as a rear glass leak. I am planning on taking it to the glass shop this spring and have them resealed. The old GM cars are also well known for windshield leaks, but mainly on the 76' and older models (full-size). Not sure about the other models.

We have had several 1980s GM cars without front or rear windshield leaks however. On the other hand, my 89' Pontiac does not have window leaks, but rather door leaks. I need to replace ALL of my door seals on that car. In comparison, my 73' Pontiac does not have any window leaks either (suprising for a 33 year old car), but it has a trunk leak from a leaky taillight seal, which I will fix this spring as well.

Well, I finally got around to changing out my antenna seal today. That soaking in hot water trick helped. I know it will fix that leak, but I am most sure my rear window is leaking too, as are my taillamps. One thing at a time.....

I had leaking into the trunk and the right rear floor. It was a leak at the upper right side of the rear window seal RIGHT AT THE POINT WHERE THE FACTORY SEALANT BETWEEN BODY AND GASKET ENDED. I suspect this leak is increasingly common at this point when the seals get old. I sealed all around when I put in the new seal. No more leaks.

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

Pete. I have water in my right rear floor as well. I will check this too. I have been told it could be a hundred different things, from the sunroof, front cowl drains, etc.

QUOTE : "I had a few leaks in my 81 300SD and found the easiest way to locate them was to get in the trunk with a flashlight while the wife sprayed various parts of the trunk area.

You are a brave person and I salute you.
Willingly getting into the trunk of a car and having your wife close the lid on you !!!!!!!
talk about a completely trusting relationship .

I also spent time in a closed trunk looking for leaks. Tail lights were most of the problem. Also found some water around the rear bumper attachments.

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.

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.

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2004 Toyota Sequoia Limited 4wd
1991 Lincoln Town Car Executive
1991 Cadillac Sedan DeVille
1988 Mercedes 300SEL
1972 Chevrolet Caprice Kingswood Estate 9-passenger wagon
1973 Pontiac Grand Ville
(Prior MB's: 1974 240D, 1985 380SE, 1984 190D, 1993 400SEL)

Similar issue but confined to this location, no moisture in trunk (!) nor evidence of migration from roof/sunroof or doors. Apparently not floor rust (at least not primary culprit) since the car has been parked during the last rainstorm. Opinions anyone? Rear window seal? (some delamination in that corner).