W211 E320 Estate Water in Spare Wheel Well

[grubber]

I have water accumulating in the spare wheel well of my 2004 W211 Estate.

I took all the trim etc out over the weekend to check for any obvious signs or witness marks and found nothing. The rear washer works fine; I operated it whilst observing and listening for leaks inside the car; there is no evidence of leakage from this system. The car does not have a sun roof.

I dried the system out using a Vax. Since drying out the boot yesterday the car has not been used but to aid my diagnosis (by good fortune) it has rained hard all day. I checked the boot again the evening and once again it is soaked. Here is my diagnosis so far:

• It can't be coming from beneath the car (it leaked without having driven the car).
• It can't be the washer system (it leaked without using the car).
• It can't be the sunroof (I haven't got one).
• The drain plug beneath the spare wheel works fine (undertray removed and drain tested over the weekend).

Any ideas would be greatly appreciated.

 

[Cole@MBS]

At a guess, I would say one of the rear light seals is leaking, or rear window not sealed right!!,

 

[grubber]

Thank you for your very swift reply. Which would be the easiest to check? The rear lights I guess? Are they easy to remove?

 

[Cole@MBS]

Five 8mm nuts on the inside of the trim, four around the rear panel, one on the inner wing.....

 

[television]

Once the lamp is off, do check the hole for any poor stamping signs , you may have to apply a little non setting mastic around the opening

 

[grubber]

Thanks for your advice. Just to double check before I take to spanner. I am removing the 2 rear light clusters, one at a time, and checking for signs of potential leaks and problems with poor stamping?

 

[television]

With poor stampings this leaves an upstanding burr on the hole so that the lamp cannot tighten down to be water tight

 

[grubber]

Thanks Malcolm. Is this more likely to be the O/S or the N/S Lamp Cluster or could it be either (or both).

 

[television]

Sadly on any hole and car, the high brake lamps were the worst where fitted

 

[grubber]

I have read several posts where the high level brake light leaks on saloons. However my car is an estate. Do they also leak on the estate models.

PS I have taken both rear light clusters off and neither is the cause of the leak.

 

[television]

It can get hard to find these things, any stamping for any lamp could have a burr on the cut out with any MB

 

[chris1200]

I have read several posts where the high level brake light leaks on saloons.

Mine does....I can hear water inside the boot lid somewhere when I open it but the process of removal to get at it sounds like too much hassle. Maybe I could drill a hole in an inconspicuous area and drain it! lol

 

[hrd123]

I had exactly the same problem which was finally diagnosed and fixed by removing the spare wheel well entirely and resealing with sealant. Job done and no further problem experianced !

I have water accumulating in the spare wheel well of my 2004 W211 Estate.

I took all the trim etc out over the weekend to check for any obvious signs or witness marks and found nothing. The rear washer works fine; I operated it whilst observing and listening for leaks inside the car; there is no evidence of leakage from this system. The car does not have a sun roof.

I dried the system out using a Vax. Since drying out the boot yesterday the car has not been used but to aid my diagnosis (by good fortune) it has rained hard all day. I checked the boot again the evening and once again it is soaked. Here is my diagnosis so far:

• It can't be coming from beneath the car (it leaked without having driven the car).
• It can't be the washer system (it leaked without using the car).
• It can't be the sunroof (I haven't got one).
• The drain plug beneath the spare wheel works fine (undertray removed and drain tested over the weekend).

Any ideas would be greatly appreciated.

 

[Frontstep]

Can you not leave a video camera running in a safe place inside the car then soak it or use a small person !

 

[ptruswell]

I've got the same problem on my W211 E280 55 plate avantgarde estate - investigations starting. It's interesting that water ingress still seems to be a problem on even more top-end cars. I reckon most cars I've had, particularly estates, suffer from this - I can remember something similar in my first car - a Marina estate in 1983! Thankfully the rest of the this W211 significantly better!!

 

[umblecumbuz]

One odd-ball situation on an estate is the sealing rubber around the tailgate opening. These have been known to leak - not the rubber itself, but water running from the roof onto the topmost rubber section and then seeping UNDER the rubber where it is a press fit onto the metal lip on the tailgate opening.

Easily checked, and easy to fix - just pull of the rubber, smear sealer along the metal lip, and replace rubber.

 

[ptruswell]

hahaha! Never got round to curing this. Problem persists having checked again this morning, so I googled and found this thread. Then I read the entry a couple of posts above this and thought "hey that's exactly my experience!" and forgotten that there is a very good reason for this - it was me!! Senior moment

It's the resulting condensation inside the car that's the real concern, especially at this time of year when you can end up with as much ice on the inside of the car as you get on the outside, if not more.

I think it's high time I gave umblecumbuz's rubber seal re-sealing suggestion a go. Only three years since suggested! Ho-hum better late than never

 

[EmilysDad]

hahaha! Never got round to curing this. Problem persists having checked again this morning, so I googled and found this thread. Then I read the entry a couple of posts above this and thought "hey that's exactly my experience!" and forgotten that there is a very good reason for this - it was me!! Senior moment

It's the resulting condensation inside the car that's the real concern, especially at this time of year when you can end up with as much ice on the inside of the car as you get on the outside, if not more.

I think it's high time I gave umblecumbuz's rubber seal re-sealing suggestion a go. Only three years since suggested! Ho-hum better late than never

Different car .... but I only realised I'd had water entering my spare wheel well after I'd emptied it looking for something else, but the water entering my tailgate had found its way into the wheel well via the trim around the lock/latch. As yours is an estate, I wonder if it could be similar to mine ie from where the chrome trim is screwed to the car.

reply #13

 

[ptruswell]

I eventually got round to resealing/resetting the tailgate opening rubber seal about 2 years ago. Took the whole thing off thoroughly cleaned all muck/grease/debris off both the seal and the flange and used 'Sikaflex 221' gun-applied rubber sealing compound gunned into the continuous 'gap' in the rubber seal moulding. Then pushed the whole thing back on being careful to orientate it the same way. Never had a problem with water ingress since. Spare wheel well now bone dry

 

[mbau]

I eventually got round to resealing/resetting the tailgate opening rubber seal about 2 years ago. Took the whole thing off thoroughly cleaned all muck/grease/debris off both the seal and the flange and used 'Sikaflex 221' gun-applied rubber sealing compound gunned into the continuous 'gap' in the rubber seal moulding. Then pushed the whole thing back on being careful to orientate it the same way. Never had a problem with water ingress since. Spare wheel well now bone dry

Hey there,
I know this is an old post but I'm the one having this issue now and I need some advice. I have a 2008 E350 wagon, and it's been in the family for almost 8 years now. I take METICULOUS care of the care, it is in almost pristine condition. I have worked on the car myself for the most part, that is why I'm stunned that I never noticed this issue. I don't know how long it's been going on, I don't know how much water has already been in and out and how much damage it might've already caused. So far I haven't had any electrical issues, and I also don't see any rust, but I'm worried that it might be rusting under the black butyl vibration dampening shield.

My first question is: If I can't find a solution, will this rust, what do you think? How long have you had this issue for, and did yours show signs of rust?

Second: What was your issue exactly, and how severe was it? So far, I've only once seen water actually sitting in the wheelwell, and that was after a day of driving in the rain, and it was not much really, just about half or quarter of an inch tall in one corner.

Also, I noticed something VERY weird. When I took the spare wheel out of the wheelwell, there were like 2 spots on the right where the water was actually sitting and the lining was wet, BUT: in other areas, the water was sitting as droplets ON TOP OF the lining! It wasn't wet in those areas, although I checked and under the lining the sheet metal was wet, but these droplets were just chilling there. What could that be? The water can't just be dripping in from exactly above as there's several layers of stuff above that are completely dry.

I have also swapped the 2 rubber dampeners out that sit next to the taillights, and all the small rubber lined clips/"nails" that hold the plastic cover around the tailgate opening.

I would appreciate any ideas as to what to do. I've read pretty much all threads about this issue and still no definitive solution. The one I read the most was the seals of the taillights, but I'm not sure if that could be causing the problem. Here ptruswell wrote about the rubber seal of the tailgate as well, haven't heard that elsewhere, might give it a shot, just want to know first whether the issue was the same, I mean the water was coming in the same way as on my car. On mine, it seems to be coming from the small holes between the sheets of metal that have been welded together in the factory, on both the right and left side on the rear part of the wheelwell (towards the rear of the car).

Thanks for the help in advance!