W203 water sloshing sound

[timosawis]

ok, so now the noise is back. We've had a fair bit of dry weather, so I'm ruling out rain ingress. The area in the engine bay I reported earlier is dry and is clearly not the fault. Heating and aircon works fine. Drains in the engine bay are clear.


No visible sign of water whatsoever, just a very strange sloshing and trickling noise from what appears to be somewhere in the dash, behind instrument cluster (?), when pulling away sharply, or on very steep incline eg car park ramp. Is this normal? I don't like the sound of it. Anyone else had similar?

My next step is probably to take it to a specialist to check it out and find the A/C drain - unless anyone has any new suggestions or can recommend easily how to access any other drains. I currently have limited access/time to do anything myself.

 

[timosawis]

hi any luck with this issue?

 

[Tomkinsm]

Coming back to this thread after nearly 8 years!

I never properly got to the bottom of this, either the noise or the location of drains. The water collecting near the brake fluid reservoir never seemed to be a problem, and I put the water noise down to the condensate in the AC draining. Neither things have given me any issue - AC worked perfectly and car has been dry as a bone.....

Until now. After all this heavy rain the water sound is back and worse than ever. For the first time water has come into the drivers footwell, and I can hear the water sloshing somewhere behind the dashboard (I think) whilst cornering. Today, driving down a steep slope my horn went off and wouldn't stop. I pulled the connections off to stop it. Then the automatic headlights played up. Expecting the car to cut out at any minute I drove carefully on quiet roads a few miles to work.

Once I could take a look I found again a big pool of water in the area below the brake reservoir, but more worryingly was the pool of water at the bottom of the fuse box. I sucked out about 250ml. The result is that the whole fuse box is damp.

Can anyone help to suggest 1. how water is getting in, and 2. how the water is supposed to drain from the area below the brake fluid reservoir

Thanks

 

[LostKiwi]

Coming back to this thread after nearly 8 years!

I never properly got to the bottom of this, either the noise or the location of drains. The water collecting near the brake fluid reservoir never seemed to be a problem, and I put the water noise down to the condensate in the AC draining. Neither things have given me any issue - AC worked perfectly and car has been dry as a bone.....

Until now. After all this heavy rain the water sound is back and worse than ever. For the first time water has come into the drivers footwell, and I can hear the water sloshing somewhere behind the dashboard (I think) whilst cornering. Today, driving down a steep slope my horn went off and wouldn't stop. I pulled the connections off to stop it. Then the automatic headlights played up. Expecting the car to cut out at any minute I drove carefully on quiet roads a few miles to work.

Once I could take a look I found again a big pool of water in the area below the brake reservoir, but more worryingly was the pool of water at the bottom of the fuse box. I sucked out about 250ml. The result is that the whole fuse box is damp.

Can anyone help to suggest 1. how water is getting in, and 2. how the water is supposed to drain from the area below the brake fluid reservoir

Thanks

There is a drain at the bottom of that compartment. A flexible wire curtain rail works well (the spiral would steel with plastic coating type normally used to hang net curtains).

 

[LostKiwi]

Just to add. The fusebox is also called the front SAM and contains electronics. Ideally you need to remove it, put it in a bag with some rice and place in the airing cupboard for a day or so to properly dry it out. Then liberally spray with contact cleaner and again allow to dry before reinstalling.

 

[Tomkinsm]

Thanks! I've never been able to locate that drain - do you know where I can find an image of it? Can you describe it?

Is it much of a job to remove the fuse box as you suggest? I need to get the car back home first....

 

[LostKiwi]

No idea on a W203. For the drains it might be easier to remove the wheel arch liner and push the wire up from the bottom.

In my 230 I just wiggled the wire around a bit from the top and it found the drain and cleared it.

 

[Blobcat]

You can also use an electric oil change pump to get the water out then have a look in the bottom to see what is blocking the drains - normally leaves

 

[AnthonyUK]

As suggested, carefully take out the front wheelarch liners and you should be able to see the scuttle drains that will no doubt be blocked with leaves.

Search for 'w203 front scuttle drains' should also show the locations you want.

 

[Tomkinsm]

Thanks

I can get to most of the scuttle drains from the engine bay - I'll rod them or blow them out. But it's the area near the fuse box / brake reservoir which baffles me. It looks like water is diverted into there, but I can see any way that it is supposed to come out? Is the drain under the wheel arch liner actually connected to that area? I'll try to get under there as you suggest and see what I can find. I've done many searches but haven't yet found any good pictures or diagrams of where this particular drain runs.

As to the fuse/SAM, I'm hoping that it's just damp/humid and it'll dry out (I'll leave it open in the sun, or get the hair dryer on it).

 

[grahamcol]

Sometimes there is so much general crud that the exit channels are completely clogged and not easy to see. I had this with my SLK. My C209 CLK, similar to the op's 203 C class also had a lot of crud around the fuse box area and l managed to clear it without too much difficulty.. Unfortunately l can't remember exactly where the exit was to that chamber but it may well have been right in the corner near the inner wing.

 

[Tomkinsm]

I managed to clear all the scuttle drains on Friday. 3 of them are fairly accessible. The fourth is on the drivers side and is tucked in just at the side of the fuse box. It's almost impossible to see - drain water drains from the scuttle, along a channel in the wing, under a plastic cover and then drops into this vertical drain. Some of you suggested clearing this from underneath. The problem with that is you can't rod it through because you'll hit that plastic cover. I cut a small hole in that plastic cover and rodded it out from the top.

With the scuttle drains clear, and after drying out the fuse box everything seemed fine.

Today we had another downpour so I was curious to see the results. Got home and found yet more water near the trapped areas around the fuse box, brake reservior and battery. I pulled out about a litre again with my syringe.

So, with the scuttle clear, it's either coming in through the grills on the top of the bonnet, or somewhere else. But the main problem is that those areas around the battery and brake reservoir seem to have no drain at all.

Attached are two pictures. I'm not fully clear how so much rain gets in there, and if it does, how it's supposed to get out??