but cannot figure out....
I know the water is not coming in from under the hood / hinge area. 2 days ago I used a coat hanger, stretched straight, to clean both the front sunroof drains.
Yet, after sitting outside last night in the rain I had water running down (weird, I know) the underdash and collecting on the floor, right next to the door sill. On both sides!
After I got motoring it started to stream down the A pillar, seemingly coming from between the headliner and the plastic pillar piece.
Is it possible that the drains are rusted? Were they plastic or metal on 123's? If rusted out, can I use some plastic tubing or something in there?
I just got done taking care of the rust in the floorboards and I'm really protective of them (ok, perhaps a little obsessive too).
I know much has been written on this topic but I feel as if I've tried every remedy previously posted.
any help would be much appreciated!

That is a bummer... maybe you need to try putting water into some places on the outside, while making sure it does not get to others.... to isolate it... not easy... or maybe get a car cover...you have a lot of money into those new floors...
How is your gasket around the windshield ?
Do you have a sun roof ... or maybe in this case a waterroof ?

You need to isolate the problem. Right before you are expecting your next good rain, tape your sunroof closed with blue painters masking tape, making sure to use three pieces overlapped on each of the four sides. Make sure it's taped very well. If you still get leaks, you've eliminated the sunroof. If not, you've id'd you problem area and you can start from there. If you pour water into the sunroof pans, can you see it run out of the drains, front and rear? You may have to angle the car to force it to go front/rear.

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1982 Mercedes-Benz 300CD
1982 Mercedes-Benz 240D - stick

We have the same problem, and we have yet to resolve it! It is coming from somewhere high up under the dash, behind the emergency brake. One thing to try (you'll need two people) is to pour a controled amount of water in to the area where you can see the water should be channeled (I also used the same method to check the sunroof). If you have the hood up, you can see the channels lead to the area beside the hood springs. I use a watering can with a long narrow spout so I can control the exact spot. Pour water in there and see if it comes inside the cabin. It does on our car. It's difficult to fix because you have to be careful not to plug the drain, so you can't do a blanket type patch (which would be useful when you don't know the exact spot). We have tried fixing it from the outside adn the inside, and our next step is to remove the emergency brake and try again from the inside (higher up).

In the meantime, I have one of those Dri-somethings that accumulates the water in to a bucket using a salt. Works quite well. I also try to either park under cover, or if that isn't an option, with the car sloping towards the passenger side. THis helps a LOT.

If you figure it out exactly, let me know too, okay?!

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Natalie

I had alot of water leaking too. It sucks.

Mine was comming in from the passanger side front door. I changed the weather stripping and drill some holes in the bottom of the door to allow water to get out of it when it gets in there. Check your doors... there should be drain holes or plugs which are covering them. Try removing them or drilling some drain holes. I was very happy when I finally figured it out.

good luck


bob

Shawnster, are there any cracks around the drain near the hood springs? Or in to the firewall?

I had another go at fixing our leak, and I had some success (though there is still a slight leak). The area right underneath the hood spring (where the drain is) was cracked along the seams (both back towards the cabin and towards the side of the car). I was going to try JB Weld but it is an impossible spot to get at. A syringe might have worked but I didn't have one. You have to have pretty small hands, and even then it's difficult. If your hand is in there, then you can't see what you're doing. Anyway, I couldn't get in there even to clean so I took an electric toothbrush (not mine ) and moved the dirt farther back so I could vaccum it. Then I put a sock (not mine ) over my hand and washed it with some solvent. Once it was dry I started covering the cracks with that metal repair tape. Hubby calls it candy wrapper, but I love that stuff! It sealed up a problem in our 280 very well. It was really difficult as I couldn't see what I was doing, but you can layer that stuff so I just kept at it and eventually I got it all covered. It was definitely leaking in to the cabin there, as covering it has improved things immensely. There is also a leak at the firewall around the cable line that leads to the hood release. I tried to cover that too, but this isn't a good method for that as the area is several depths. So, it looks like we're still having to take the emerg brake off and try to repair that area from the inside.

Anyway, check it out. Both Belinda and our parts car are rusted in these areas, so maybe it's a weak point (the parts car is REALLY bad).

Good luck!

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Natalie

yesterday I parked nose down in the drive way. First, I opened the sunroof and poured water into the sunroof channel from a watering can with a narrow spout. I really drenched it. 99.9% came streaming out of the drain in the door jamb. A drop showed up on the headliner near the top of the window, in about 5" from the A pillar. This was true for both sides. Then I parked tail down in the driveway and repeated the experiment. Water came streaming out of the rear drains, no leakage detected into the rear footwells.
Then I opened the hood and poured water into the seam under the hinges on both sides: it came pouring out of the drain in the wheel well, none in the cabin at all.
Then I closed the sunroof, took the hose and directed a steady stream on the roof between the windshield and the sunroof. Sure enough, it came streaming down the inside of the A-pillar and started to collect in a puddle on the floor. I inspected the windshield seal in the upper corner: sure enough, on the driver's side I could literally stick my finger in the gap and on the passenger side I detected a smaller gap up in the corner.
So, my windshield guy who has resealed twice now is on the hot seat again, I go to see him today.
Hope this helpful to somebody.

jassz
I was visiting a local shop last winter and he had a 300D in there and could not find the water leak. I showed him all the usual suspects. He cleared all the drains and it still leaked right down the firewall in front of the driver. Returned it to the owner. Got it back two weeks later and it was still pouring water inside.
Then I was out and he was scratching his head and saying some bad words. Suddenly the lights come on and there was the problem.
There is a large black plug on the firewall that the wiring harness and some vacuum lines go through. It was a little out of place. So we pushed it back in. Then water tested again. No leaks. I called him this morning and he said zero leaks with that car since.
Just one more thing to check.

Shawnster, the upside of it being the windshield seal is that at least now it's someone else's problem too. :p

Old Deis, we DID have a leak at the spot you described (the gifted previous owner had deliberately pushed it aside to run the radio wire through to the battery ). It did improve things when we re-secured it, but there is still a problem. It is rusted beneath the hood release cable, and I'm pretty sure that's where it's getting in.

Hopefully we get it resolved before the rainy season hits. That's usually July around here. :p

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Natalie

A new windshield seal is available. When I had my windshield replaced a few years ago, it was about $60. I furnished it to the windshield place. It was made by Conti, the big rubber company. The other place to check for leaks (if maintance hasn't been done properly in the past) is underneath the battery tray. A leaking battery can eat through the firewall.