W126 Where is this water coming from!?!? - PeachParts Mercedes-Benz Forum

bodyart27 · #1 07-09-2007, 04:00 PM

***SEE POST # 14 FOR PICS OF THE FIX*******

Just got back from a road trip to Houston (from Dallas) and when unloading the car last night I noticed the carpet behind the driver's seat (where the rear floor mat lays) was saturated. Real wet. Pulled back the carpet and put a fan in the car overnight (still damp this morning). Not rusty - had to be recent.

Hmmmm. I opened the sunroof and poured water into the rails on both sides (poured in the middle). Car took a pee onto the pavement from the rear wheel wells. Drains were not clogged. That seemed right.

I got nailed in a rain storm in Houston driving in on Friday, and overnight sitting in a parking lot. Maybe a door ajar? Window cracked? Water forced in somehow?

Initial look at the trunk - looked dry. I can't recall anything (like a water bottle) that could have leaked back there.

If water came in on the back edge of the sunroof - where does it go?

Can condensation from the A/C get back there? the front floors / floor mats are dry.

Any thoughts? Something to look for? I guess if it only does it once I'll rack it up to a door/window ajar?

Douglas.Sherida · #2 07-09-2007, 04:23 PM

Water can get in at the firewall, either through the windshield seal or through rust holes (especially around the hood hinge wells and their drains).

It runs under the plastic channel where the vacuum tubes are and pools in the rear floors. It can be very hard to find evidence of water passing through the front floors.

Palangi · #3 07-09-2007, 04:41 PM

On a 123, water from the A/C evaporator drain will pool in the drivers side back seat floor. I assume a 126 may be similar. On a 123, pull the passenger side kick panel and reach in there way up forward on the centerline of the car over the hump. Grab hold of the foam tube which is the evap drain hose. It will crumble to powder as soon as you touch it. Either get a new hose, or fabricate a custom funnel out of a plastic soda bottle to serve the purpose.

justinperkins · #4 07-09-2007, 05:06 PM

I feel your pain, I'm trying to track down a newly discovered sunroof leak on my wagon that these crazy rains have brought to light.

Good luck with the hunt.

JimmyL · #5 07-09-2007, 06:02 PM

I've darn near given up the fight to find the leak on my '85 wagon. Have you ever seen cars that leak like these freakin things!!!!!
Somehow, mine leaks on the drivers side of the sunroof, runs down from about the middle of the sunroof. It runs along the underside of the headliner [top side against car roof that is], runs down to the A-pillar, and drips down that onto my parking brake lever and hood pull handle. I believe it also makes it's way down the B-pillar, gets that carpet wet, and just creates a very large pond under the driver's seat. Also the rear carpet on the tranny hump is soaked on the driver's side.
Sunroof drains appear to drain. The front connections from sunroof to drain hoses is fine, and does not drip at all. I have sat in the car with the front trim cover removed and headliner peeled back a little, and water is coming middle/or back to front. What is it with these freakin cars.

I got weed eater line to feed out the front tubes easily. I had to try and shove it up the rear drain from the back{

} as you can't really get to the rear drain opening, only the exit. My weed eater line was not stiff enough to make it up through the channel, but water poured into the sunroof area drains back to the rear exit.
I'm at a loss also......
I'm sooo happy China has no sunroof!! She might end up being a keeper!

Ryan Z · #6 07-09-2007, 07:32 PM

On another forum, a guy kept getting water inside car. His problem was the A/C drain. Either broken or clogged. Fairly easy to check.

crashone · #7 07-09-2007, 10:46 PM

On the 126 there are 2 drains, one on either side of the hunp by your feet. They are foam and will fall apart. Take the side kick panel off the driver's side and you will see a drain tube coming out of the evap box. Check and make sure it is intact. I made a new one out of clear 5/8'' ID tubing and works fine. These drain out into the tranny tunnel. But then you say the front is dry so maybe not the AC drains. Check for leaks around the rear window gasket, check the antenna gasket for failure. You can lay newspaper down in the trunk and spray outside with hose to check for leaks. Good luck.

Lycoming-8 · #8 07-10-2007, 12:12 AM

Another location to inspect for water leaks is the corrugated rubber connector that covers the vac lines and electrical wires going into the four side doors. I am sure that the one on the front passenger door has caused my front floor wetness. Also the way the car is parked can change the location of the pooled water, ours is always parked at home with the nose pointed down hill and there has never been a drop in the back footwells.

JimmyL · #9 07-10-2007, 01:09 AM

Quote:

Originally Posted by Ryan Z

On another forum, a guy kept getting water inside car. His problem was the A/C drain. Either broken or clogged. Fairly easy to check.

You are correct, it IS easy to check. It fills up with water just sitting out in the driveway. I've had the evap box foam tube issue before, but this isn't the case.
That was good info though, but alas, it isn't my issue.....
It isn't my rubber door pieces, as I have water in my head liner.
Gee Shell, I'm walking all over your thread! Sorry.....

I hope this info applies to you maybe....

bodyart27 · #10 07-10-2007, 09:47 AM

No problem Jimmy. At least I have a place to check (front A/C drains).

That might be the issue as it didn't rain yesterday and it still is very damp (ran the A/C in my commute).

Sound like aftermarket tubing will work? Nothing MB specific needed (like a weird size)? Hopefully I'll have time tonight to pull the kick panels off both sides and get a good look.

Feel pretty lucky I caught it right away.

loneranger · #11 07-10-2007, 07:20 PM

may be rusted firewall under hood hinges if drains are plugged. also body wall will rust out next to fender. Remove battery tray and have a look, if looks bad suggest you pull fenders and look. This can be repaired with epoxy/fiberglass cloth. Will leak some if rubber boot on vac lines rots but if you have ducks swimming in the rear floor pan you have large rust holes in fire wall/inner side panel. water runs under sound damping material in front thru hole in seat mount to rear floor.

Hatterasguy · #12 07-10-2007, 07:21 PM

Quote:

Originally Posted by bodyart27

No problem Jimmy. At least I have a place to check (front A/C drains).

That might be the issue as it didn't rain yesterday and it still is very damp (ran the A/C in my commute).

Sound like aftermarket tubing will work? Nothing MB specific needed (like a weird size)? Hopefully I'll have time tonight to pull the kick panels off both sides and get a good look.

Feel pretty lucky I caught it right away.

Let me know how it goes and post pics if you can. I need to change mine as well.

bodyart27 · #13 07-11-2007, 10:05 AM

Definately no rust under the battery tray. When I replaced the battery to a 34R optima I pulled the battery tray, cleaned it up (knocked off surface rust and repainted).

I called Park Place Dallas (dealership) - amazing they had the A/C evaporator drain tube in stock (man they carry a lot of inventory for old cars) for the the driver's side. The passenger they could have by noon next day if I needed it (it's only wet on the driver's side).

So, I swung by last night on the way home, $28 my cost. I can't say I'm too impressed with the engineering of this part (I'll post pics later).

But, long story short, I pulled the panel back, found the tube easily and installed it. The old tube had deteriorated to the point where I could see the inner coil spring that is inside the foam of the drain tube (inner spring is there so it doesn't collapse as there is a wiring that crosses over it). I really think this could be designed better. But, then again, it lasted 23 years. If you click the "buy parts" link and look up a/c evaporator tube you'll see what I'm talking about.

http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1ZO0K1NU424P0LN0YX&year=1984&make=MB&model=300-SD-002&category=R&part=A%2FC+Evaporator+Drain

Hopefully in a few days I can report back that the car is "dry."

Hatterasguy - I'll post some pics probably this weekend when I get some time.

bodyart27 · #14 07-14-2007, 04:39 PM

So finally got some time to add some pics.

First pic is just the new A/C drain tube.
Very odd construction - not too impressed, but the original did last 23 years.
Inside the spongy foam tubing is a spring that prevents it from collapsing.
There is a wiring harness that goes across the tube, so I guess the engineers wanted to be sure there was no condensation on the outside (thus the spongy foam).

As you will see in the pics, you remove the kick panel (and the panel that goes above your knees under the steering column) to see the drain tube.
Not too bad. For orientation, that is the gas (diesel?) pedal on the left of the picture.
There is a wiring harness that is strapped with a reusable zip tie over the drain tube.
I suggest unplugging the top connector and loosening the zip tie to make it easier to remove the tube.
There is a ivory colored ring clip at the top of the tube.
The tube had deteriorated so much that I just pulled the tube off the connector at the top, clip and all.
Then I undid the clip (hinged on one side, just a hook clasp on the other).
The clip is pretty darn tough to clip putting the new tube on.
The drain fitting on the A/C condenser has a little lip (like on a radiator).
The clip goes past the lip (like putting a hose clamp on a radiator) so the tube won't back off.
You thread the tube under the wiring harness and poke the rubbery end into the transmission tunnel. That's all there is too it.

I have had some wood blocks under the carpet to get the SD to dry out. So far so good!

JimmyL · #15 07-14-2007, 05:09 PM

Wow, that sure is different from a W123!!

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode