W111 sedan trunk leak / drain questions...
 

I'm working on waterproofing the trunk of my 1963 220S. Today I got grumpy but compliant husband to get inside trunk with a flashlight while I sprayed water all around (pretty good deal, no?). Here's what we found:

1. Trunk seal is leaking just about everywhere, no real surprise there

2. C-pillar vents - if I hose water in there it comes pouring in along sides of trunk interior and drains out the currently unplugged hole at the bottom of both of the side wells. (Rubber mats are all removed).

3. Trunk hinge area - if I hose water in there it seems to go into a rubber tube and then still come out along the sides of the trunk as with the C-pillar vents.

I assume that the hose is putting out more than an expected amount of water for a rubber drain line to deal with, but I also assume that something is wrong.

I don't have any idea how either the trunk hinge areas or the vents are supposed to drain, so I defer to those who know more and ask for some suggestions...

thanks
Scott

I don't think either are supposed to drain since they are not supposed to get wet.

The water may not be entering the trunk through the vents but through small rust holes that have developed where the chrome attaches and/or around the bottom of the rear window seal. The only thing to do is plug with with some silicone sealer or major body work.

But first you have to find them. This is just a project, but you will be glad you did it as the 'built-in' cure is for the spare tire wells to rust out. You will have big holes in the bottom of the wells, but your drainage problems will be gone for good!

Well the C-pillar vents clearly aren't setup to have a hose aimed at them, but water will enter in the rain. As for the trunk support hinges, the space that those go into is designed to catch water and drain as that section is exterior to the trunk seal.

Oddly enough, I don't think this is the case. The seal is old and I know about what happens with rotten windshield seals. This isn't that.

All of those tubes are doing exactly what they are supposed to do. Be thankful that they are not rotten and thus not directing the water where it is supposed to go. You probably need a new trunk lid gasket. If you have a sunroof the rear sunroof drains also go into the trunk near the wheel arch. Do not remove or plug the tubes or you will have water going where it should not. Make sure that the rubber drain plugs in the wells are clear.

Are you saying that the car is designed to have water flow from the tubes down the truck side of the wheel arch into the wells on either side and out the holes in the bottom???? Really????? How well does that work when there is the rubber mat in the left wheel well area?

Is this a sunroof car?

No. Attached are pictures showing the water flow inside the trunk. Is this _really_ "as designed" ????

Yes. Water that gets past the seals incidentally is directed by the tubes to to wells and out the drains. Of course there isn't supposed to be a lot of water getting in there. It is fail safe. In sunroof cars there is almost always water that gets there. There is also a drain in the upper wheel arch.

But if you look at the first picture in the previous post you see that the supports for the trunk are OUTSIDE the trunk seal. So lots of water goes into that area when it is raining... Is there another seal missing that I don't know about?

Perhaps that is part of my problem. Can you tell me more about this drain and what is supposed to come out of it and how to find it?

Thanks

Yes and no- The drains in the hinge holes are doing their jobs, but there should be plastic or rubber drain tubes attached to a drain snout that comes off those hinge holes. Hunt around- they should be pointing slightly off inside the "cage" towards the inner fender on each side. The tubes should be directing water to a hole (which should have a little cover over it) in the rear fenderwell behind the tire.

This is also where the water taken in through the c pillar vent should drain.

Either you're missing the tubes, the drain to the outside in the fenderwell is plugged, there's a lot of debris down inside the frame area holding moisture, or a previous owner decided that none of that was really needed, anyways, and just did away with it.

Those holes that are acting as drains now actually came with rubber blanking plugs from the factory, so no, they were only meant as an emergency measure.

Hope this makes sense and kind of helps.

I will hunt around. I also have a parts car that I can hunt on... Except previous owner carpeted EVERYTHING in the trunk so that probably won't be much help...

What's funny is that I already ordered the rubber blanking plugs for the holes and haven't installed them yet. Yes, it makes sense and kind of helps. I'm guessing the drains to the wheel wells are clogged. I wish I could find an image in EPC or something that shows the path better...

Scott

Volume 3 of my Heckflosse manual is out on loan to my body/ paint guy. I will see if I can dig up my W111 "crash" guide- hopefully there will be a detailed pic in there.

Meanwhile- do you have the parts book that came with the owners manual? You could try consulting that.

Oh that would be wonderful if there are pictures....

You mean the "Catalog B" or whatever it is called I think. No, I don't have it, but I might have one from a 110... I will search about.

Yup- the 110 one will be the same setup.

The holes in the bottom of the spare tire well are there on a lot of older Mercedes. If you ever do get a lot of water in the car you pull them out and drain the water.

But the plugs dry out and fall apart. Then water gets in as you drive on rainy days and the bottom rusts out. This is very bad on 123's but all Mercedes from that era have this problem.

The solution is to buy new plugs and replace them when you notice them drying out.

These holes are not unique to Mercedes. Porsche also has them and so do VW's from that era. It's a German thing.