SEC W126 leaking boot - latest info

Hi, I've read several threads about the leaking boot problem. Mine has it too and needs the outer panel below the rear window replacing. For my benefit and the benefit of other members, I'd like to summarise the problems and solutions so all the possible causes are in one place and easily accessible? Am I correct in my summary of the problems associated with water in the boot? Can you add any more causes? Please give us all the benefit of your experience.

1. Rear window seal permits water ingress, the panel below the window (covered by the boot lid when shut) rots and eventually the inner panel rots too.
2. The boot seal itself may permit water
3. A badly fitted boot-lid also may allow water in
4. Regardless of the above, condensation in the boot-lid itself will always mean the boot is damp if left outside in winter. Obvious when you opne the boot-lid and water runs out.

Possible solutions
1. Replace the rear window seal. If the panel has started to rot a good seal may not be possible so it will need repiaring/replacing.

Question1. Does Mercedes or anyone else sell a replacement outer panel? Any links?
Question2. Can a bodyshop make up a panel or fit a factory one, can anyone offer a rough cost and recommend a bodyshop who has done such a repair?
Question3. Does the inner panel (appears to be structural?) ever need replacing and if so the same questions as above?

2. Replace the boot seal

3. Refit the boot-lid

4. Presumably the only solution is to garage the car?

Any latest info on this problem will be greatly appreciated.

Stuart

 

Its generally not the boot lid or boot lid seal itself that will let the water in.
Its always the rear screen.
It dribbles past the screen seal and sits on the underlying panel before eventually rotting it out. This is common to nearly all Mercedes of this era, and is a well documented design flaw.
I found a post on the web once of a guy who rebuilt that panel entirely out of filler and JB weld!
Catch it early and its not too bad. Its a ball ache to put right as the screen has to come out, and the repairs have to be done properly to get the profile right so that the screen sits correctly.
Use tons of sealant when the screen goes back in!

 

Thanks, mine is already bad. Presumably then there are no manufactured panels, it's a bodyshop job?

 

As far as i'm aware, i don't think theres a panel available, though i might be wrong.
You could tackle the job yourself, but you'd need to be pretty competent with a welder and have some degree of skill to get the right finish. If you got it wrong, chances are the same thing would happen again a few years down the line.
You'd probably won't see much change from a monkey (£500) to have it done right in a decent bodyshop.

 

Yeah that's what I thought. To strip the window, make up a panel, remove the old and weld in the new one, new seal and window in has to be that sort of money I guess. But I have to do it or the car is scrap and it has just passed it's MOT! And believe it or not, everything works on it!

 

Removing the rear glass is easy ,simply a matter of removing the sail panels ,disconnect the two wires for heated window ,and simply lay on your back on the seat and push it out with your feet(as long as no one has used silicone etc to seal it) it will come free of the body.
The replacement panel is about $75 USD from mercedes.
It's spot welded in each side to a panel which also holds the hinge in place. A few spots hold it to the parcel shelf panel. if you buy a new panel you can see how its welded into place so removing the rusty part is easy. It's not structural so it can be done easily by a competent handy person at home.
The glass is the expensive bit ...

 

Thanks for that. I just bought a repair panel from Mercedes, 72GBP. I think that's pretty reasonable for a change but the window seals aren't, there are 2 of them, 100 and 170! Ouch!

 

Is this worth doing pre-emptively? My back window seems pretty tidy, and although there is one very small bubble at the bottom and no sign of trouble inside, is it worth taking the glass out now to check and tidy up any surface grot? It's a 300SE saloon, not an SEC.

 

Update. I got the panel fitted for £150 and I didn't replace the window seals on the advice of the fitter who charged me £80 cos it was a pig to get out. Being laminated they couldn't apply the usual 'boot it out from inside the car' trick.

Anyhooz, it's back in, nicely sealed, the panel is painted and total cost was £300. Was it worth it? In hindsight I should have sold the car the moment I bought it, needed welding which I didn't know until the MOT came up (£400), this panelI knew about but thought I'd bodge it which you just can't do, and now the gearbox is slipping badly. So I'll end up having spent much more than the car is worth but, touch wood, that'll be the end of it ....for a while!

 

I'd say it was worth looking Tog. The parcel shelf on mine was badly rotted and it was obviously spreading rapidly being quite thin metal. Remove the rear parcel shelf trim first and all may be revealed. Then if you have to go further it's window out to see the full extent.You could do it yourself. If there's any rot and you're keeping it long-term, it's worth it.

 

THIS HOW TO DO IT PROPERLY. http://www.mbclub.co.uk/forums/mbclub-projects/60611-sec-widebody-conversion-11.html

post 122=before

post 166 onwards the after