HELP! Water in spare wheel well

[123qweasd123]

Help! Water in the spare wheel well in my on my W211 estate. I sealed the top (pic 1) should the 2 sides (where I’m pointing) be sealed too? To the outside edge. Thanks

 

[mioba]

You dont need to seal anything but make sure the seals are intact.
If its in the actual wheel well have you been driving in torrential rain. There is a clever water valve in the wells which as you drive takes any water out of the well.

 

[mioba]

welcome to the forum, stick around and post the solution

 

[123qweasd123]

You dont need to seal anything but make sure the seals are intact.
If its in the actual wheel well have you been driving in torrential rain. There is a clever water valve in the wells which as you drive takes any water out of the well.

Thanks. Car has been stood, not been driving it in the rain. Seals are intact (bit dodgy in places but ok) but they don’t seem to be sealing anything!

 

[mioba]

The fat ones are the rain seals and not what you are pointing to/highlighted. the fat ines seal by being squashed when yiu close the boot.

Get in the back, close door, have someone hose the door down to see where water enters.

 

[Wighty]

Pull the rubber seal off and put some silicone sealant underneath then push the seal back on .

 

[mioba]

Pull the rubber seal off and put some silicone sealant underneath then push the seal back on .

which rubber seal. Thats the question

 

[Wighty]

which rubber seal. Thats the question

The one that goes all around the boot opening .

 

[mioba]

Just a thought. Would silicone not be too harsh due to the chemicals in it. Roofing mastic is surely better as it is rubber based.

 

[123qweasd123]

All the sides of the boot and interior tailgate are dry, the water only appears below the spare wheel so must be running behind the trim somewhere. my guess is it’s running where my finger is and into the boot but I’ll take off the interior trim as best I can and get the hosepipe out, will update…

 

[mioba]

i am thinking it it could be a rear light seal. not sure how they are sealed on the 211

 

[123qweasd123]

i am thinking it it could be a rear light seal. not sure how they are sealed on the 211

Had a look as best I could but hard to see with trim in place, will let you know thanks

 

[mioba]

Had a look as best I could but hard to see with trim in place, will let you know thanks

hose them down

 

[Wighty]

Just a thought. Would silicone not be too harsh due to the chemicals in it. Roofing mastic is surely better as it is rubber based.

Well remembered, I think I used RTV sealant when I did my E class rear seal and lights

 

[peterws1957]

Just a thought. Would silicone not be too harsh due to the chemicals in it. Roofing mastic is surely better as it is rubber based.

Would be ok if none acid based which can cause corrosion when mixed with water.

 

[M80]

I've sealed these tailgate lip seals with silicon for years, no issues that I can see.

On the S211 there are side trims that run top to bottom. They are held by a rubber 'rawl plug type' of push in, with plastic pins into those. If water is getting past those, under the trim, it would cause your issue.
A bead of sealant around the top of those to direct water away should do it. The trims are awkward to remove as they sit around the dampers at the top.

 

[brandwooddixon]

Bite the bullet and remove the interior floor trim so that you can actually see where the water is coming in.
Puff a light layer of talc over the floor, shut the boot and pour water around the boot edges, rear fixtures such as number plate and the rear lights including those on the boot . The talc will show up the water as it tracks to the wheel well. You can then remove side trim to see where it is coming from - dictated by the results of the first soaking.

Typical points of ingress are sunroof (they all leak to an extent) but the drains can become blocked or leak, light fixtures and then boot seal (the thick rubber one).

 

[123qweasd123]

Thanks all for your help so far, really appreciate it.

Found something! Corner of this vent, then disappears under the glued down black plastic. Offside, behind net storage area.

What’s the vent? Stop suffocating? Silicone around the edge of it or try and fix at the point of ingress on the exterior of the car?

Water also pooled at base of the battery (same side).

Thanks!

 

[M80]

Another ingress point is at the shark fin roof antenna.
Peel down the rear roof liner and see if there is evidence of wet cardboard.

 

[brandwooddixon]

Thanks all for your help so far, really appreciate it.

Found something! Corner of this vent, then disappears under the glued down black plastic. Offside, behind net storage area.

What’s the vent? Stop suffocating? Silicone around the edge of it or try and fix at the point of ingress on the exterior of the car?

Water also pooled at base of the battery (same side).

Thanks!

It's to ensure airflow through the boot area, or at least to the back of the trim where condensation can build up.
The other side is hidden behind the bumper.
I'd forgotten about those, but recall that there are certain cars (not just MB) that this is a known issue.

Worth checking that water ingress is actually the vent and not above it.
If its the vent I guess that you're next step will be to remove the bumper in order to seal it from the outside. There's likely one one on the other side as well. A pain to remove the bumper, but it will be easier to apply a lasting fix.