W124 estate window leaks?

[Paul64]

I wonder if anyone has had water leak problems into the area behind the back seats of their 124 estate?
We've had some pretty bad rain here and I didn't notice till this morning when I removed some papers from behind the left hand side against the back of the rear seats that turned out to be wet....
This also combined with a erratic function of the IR door locking (controls under the rear bench seat methinks) all comes together now.

I am leaning towards the problem lying with the rear side windows of the estate section - has anyone had the same problem and solved it by resealing the glass - rubbers and sealant??

Thanks

Paul

 

[millo777]

Both of the w124 estates I've owned have leaked through these windows. On both, the seam under the window rubber has rusted quite badly. You'll need to take the windows out, fix the rust and re fit using new window seals, and possibly non drying windscreen sealant.

I fixed the problem on my current car and stupidly reused the seals, and it's started leaking again, so I'll need to do the job again. They are expensive, £117.72 for each side, and thats with 10% off. part numbers are A1246702039 right and A1245701939 left.

 

[Paul64]

Hi Millo,

Thanks for the heads up - I shall order a set up and get the de-humidifier out of storage...

Paul

 

[kth286]

some people have found very bad rust under neath, which has required replacement metal welded in.

 

[Paul64]

Oh well, looks like another little project though I'm hoping with the lack of salt and general sunny weather here, it won't be too bad....

Paul

 

[bolide]

It's worth pointing out that the seals don't leak - it's the junction between the seal and the glass, and the seal and the body that leaks

I'd try drying the car out and using mastic before removing the windows. It's a bigger job than it looks and the aluminium trims are a swine to remove without them bending - and a bigger swine to replace afterwards

Nick Froome

 

[hotrodder]

Have you had much luck with that approach Nick? I've been putting this job off on mine as i know it'll be horrible, obviously doing so will only make the corrosion worse but i would have thought that once it's started it'd be a losing battle as the corrosion will be lifting the seal

 

[219]

A quick check you can do is to remove the side panels in the boot which cover the spare wheel on the left and the access to the washer bottle on the right - you can then look/feel up behind the inner metal panel and check for rust below the windows .

On one of my estates , the ingress of water had also started rust where the wheelarch joins the inside of the quarter panel below these windows . The car still looked fine outwardly , despite these hidden problems .

There can also be problems around these windows caused by sacrificial corrosion where alunimium meets steel .

If all looks clean and dry in there , you may not have too big a problem , but if you do find rust in there it can be a big job to sort out .

I have similar pleasures to look forward to since the rear windows on both my W126's are leaking and rotting the rear shelf below .

 

[Paul64]

Got bored this afternoon so attacked the seals with gusto.
Cut the old ones out with a stanley knife and some gentle persuading but all went well in the end. The ally panels came out undamaged - the hardest part was getting the remains of the original sealant off the glass... Acetone wouldn't touch it so had some adhesive remover which seems better - still progressing that.
The frame was in pretty good condition - I cleaned off the recess with a screwdriver blade and a wire brush and cleared out a few flakes of rust but nothing dramatic.
The lower edge had a little corrosion between the sheets of steel where they were spot riveted but generally, condition was good.
I coated the whole lot with plenty of rust converter and dribbled it down between the two (and three in places seemingly) pieces of steel to protect that and now, I just need to order up some window mastic before the seals arrive on Wednesday - anyone have any favourites for that? Is there some 'Special' Mercedes product to use or is there just a Sika product that does the job at half the price??

Hopefully this will be the end of the problem - water was in the gulley at the bottom where the seal sits and, quite a bit of the original sealant had lost adhesion however, there seemed to be two products in use - a gray sealant between the rubber and the steel and, another black product between the rubber and the glass: Is this correct?

So far, I would suggest it's a 4/10 for difficulty though my ally trim came off pretty easily.
As Nick mentioned, I can see the install being a bit more of a challenge...

Paul

 

[carat 3.6]

I've got the same problem, spent most of the afternoon removing the carpets and drying out the car. Looks to be the passengers rear window that leaks, about 3 pints of water in the foam under the carpet.

 

[millo777]

@Paul64, as far as I'm aware, they didn't come with any mastic typre sealant on these windows form the factory, just the rubber seal, so anything in there was previous attempts to fix the leak.

I didn't find installing the ali trims hard at all. Slide the leading edge of sloping part into position so it fits into the seal properly then worked back from there tapping it in with a rubber mallet. 5 mins a side. I doubt this is the official way of doing it, but it worked fine and the trims didn't get damaged.

If anyone has any tips for useful products for stopping the leak, they'd be appreciated. The carpet behind my drivers seat is damp....and with no garage to work in and torrential rain...oh joy. I may have to try and plug the leak with the windows in situ this time and replace the seals in the spring.

 

[bolide]

The leaks come from a number of places:
* blocked drains under the windscreen
* splits in the firewall
* rust holes in the front footwell floor or firewall
* broken or missing plastic moisture barrier behind the door cards
* dislodged or rotten aircon drains
* misrouted or dislodged sunroof drains
* leaks from the load area windows
* leaks through the floor above the rear exhaust silencer
* leaks through the body of the electric aerial
* leaks round the grommet of the electric aerial
* leaks into and via the tailgate

If your car leaks you may have a gallon or so of water under the front carpet mats. This will evaporate then condense again and work its way round the car

Best way to dry an estate car out is to park it slightly nose-down, remove the front carpets, lift the rear seat squabs, open all the panels in the load area and leave for three days with a dehumidifier running 24x7

Nick Froome

 

[GP801]

Its amazing how much condensation forms. Couple of years ago I thought I had problems with the rear window seals. Boot was wet under the folding seats and a little under the rear seats but nothing in either of the side wells in the boot. Left it for a couple of days in the Tuscan sun to dry it out and have had nothing since. I think over the years it was just a build up of condensation.

 

[bolide]

Amendment: Best way to dry an estate car out is to leave it for a couple of days in the Tuscan sun whilst drinking Sangria by the pool

Nick Froome

 

[GP801]

Amendment: Best way to dry an estate car out is to leave it for a couple of days in the Tuscan sun whilst drinking Sangria by the pool

Nick Froome

Sangria in Italy! Shame on you Nick. Prosecco every time.

 

[Paul64]

Well, got the new seals in and the glass back in - went OK I guess but when I tried testing with a garden hose, there was an immediate small leak showing at the front lower corner inside....
Attacked the seal with a load of Sika that's waiting to go off - hopefully that's going to sort it.
Bit disappointed with the original job I did as it all really went together pretty well.... Oh well, I look forward to the next test of faith - bring it on!

Paul

 

[Paul64]

Heineken on the terrace in the sun was OK - Italy perhaps in the summer....

Also changed the front discs and pads to get rid of some vibration under braking, did the joint under the fuel pump to stop an oil leak and changed the indicator relay which was causing the fast repeat of the lamps (except on hazard setting..!) and, put the winter tyres on again - Continentals that proved excellent last year.

Ready for the trip to Alsace for Xmas next weekend, 2000km here we come!

Joyeaux Noel to all....


Paul

 

[paulmaccas]

hi im breaking a few w124 E class mercedes cars so if need any parts call 07817 369670 or email [email protected]

 

[millo777]

Another point that might be of interest, if your w124 estate is leaking, don't leave a rigid plastic boot liner in the car. Mine lives in the car as I don't have anywhere to store it. It must had trapped some moisture underneath it leading to some mold growth on the fold out seat back and the hinges for the 2 cargo are floor comparments more or less seized solid.

It also seems very odd that in both w124 estates I've had, the water gathers in the passenger foot well while the drivers side remains bone dry. Is there any reason for this?

I need a quick fix on the cargo area side windows until spring when I fit new seals. So, whats the best option, attempting to get sealant between the seal and the car body?

I'll also renew th emoisture barriers behind the door cards. Whats the best adhesive to use for this? is aerosol contact adhesive o.k?

 

[shivayasharecat]

@Paul64, as far as I'm aware, they didn't come with any mastic typre sealant on these windows form the factory, just the rubber seal, so anything in there was previous attempts to fix the leak.

I didn't find installing the ali trims hard at all. Slide the leading edge of sloping part into position so it fits into the seal properly then worked back from there tapping it in with a rubber mallet. 5 mins a side. I doubt this is the official way of doing it, but it worked fine and the trims didn't get damaged.

Hello, did you find this job easy with the new rubber seals?