W124 leaks in the rain on the "A"-pillars - PeachParts Mercedes-Benz Forum

johnscars · #1 02-16-2009, 01:36 PM

While driving fast in a rain storm, a 2-3 inch long wet spot will form on the round fabric between the windshield and the front side windows. I noticed it when it started dripping onto my left leg. It occurs right next to the joint where the 2 "A"-pillar molding parts join (the lower molding part has the VIN badge). It looks like water enters up the sides of the windshield, into the roof, then runs down the "A"-pillar. Or rain water may be forced to the sides of the windshield and directly into the "A"-pillar. The car has a new windshield installed by the PO. And when I run my finger up along the windshield's outside rubber side-flange, there is a slight bulge (1" long) at about the same location on both "A"-pillars. But the bulge's rise is pretty slight, and there are no obvious openings. There is a very small opening in both top corners of the windshield where the rubber side-flange transitions from the glass to the body. Maybe the windshield installer missed something. but it smells awfully coincidental that it's happening on both sides, and at the same spot.

I can caulk the holes, but I'm a little concerned about hidden rust growth. Anybody experience this or looked into it? Car is an 87 wagon.

johnscars · #2 02-16-2009, 02:32 PM

As luck would have it - it started pouring rain and my daughter needed a ride. So...the fabric didn't have time to soak it up and get wet, but 8-10 drops dripped out right where the 2 trims join at the windshield roofline. They dripped when turning. And they dripped from both "A"-pillars.

Is there a way for the sunroof compartment to leak into the "A"-pillar? Is there a drain down the "A"-pillar? Thanks for any help.

milner351 · #3 02-16-2009, 03:12 PM

I've had a similar issue in my '95 - only on the driver's side.

I have no way of knowing if my windshield has been replaced or not - my moonroof does not work - but does not leak either (around the roof opening anyway) so I'm a bit paranoid to mess with it.

Jeremy5848 · #4 02-16-2009, 04:03 PM

The sunroof drains on the '87 300D Turbo (W124) are at the front of the sunroof, one each left and right, and are supposed to drain down into the front wheel wells. It is possible that a clogged drain could allow water to pond and seek another outlet.

There are many threads on various methods of cleaning out the sunroof drains and the search function will bring them up. I have had good luck with the plastic line that line trimmers use.

A leaky front windshield seal would be my second guess but I have no no experience.

Jeremy

patbob · #5 02-16-2009, 04:13 PM

I'm not sure if this is relevant to an '87, or even in your case, but also check the cheap thing -- missing screws in the front rain gutters. On mine, I found those screws have through holes into the A pillar and some missing ones were letting water in there. It'd come out under the dash where the pillar is welded to the rest of the car, but only when there was a lot of water or pressure forcing it in. It would drip down the inside of the panels to the floor.

johnscars · #6 02-17-2009, 12:56 AM

Thanks for the replys. Jeremy your suggestion brought up way too many threads of sunroof drain leaks to not look there first. I'll try to clear the fronts tomorrow. And I guess I'll have to go to pull the headliner trim to get the truth on rust. Thanks for the redirection. Lots of suggestions for cleaning the 4 sunroof corner drain tubes with weed-wacker line or bike brake cable - and the need to clean out the lower drain grommets (fronts are by the door hinges.) One post said it appears MB used too-short plastic tubes (and they shrink) on the 87 wagons. And he detailed the need to remove the panels from windshield trim, pillars, kick sides and rug to correctly route new plastic tubes. I may need to order new plastic drain lines. If so I'll try to shoot/post pix, so check back if you're interested.

John
87 300TDT 281,000

Jeremy5848 · #7 02-17-2009, 02:58 AM

Quote:

Originally Posted by johnscars

. . . 4 sunroof corner drain tubes . . .

I read that too but dam' if I can find only two at the front and I poked around for half an hour last fall. We need to hear from a real expert: does the '87 300D Turbo (sedan or wagon) have two or four sunroof drain holes? And if four, where the heck are the ones in the rear?