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Old 01-01-2012, 10:32 PM
Rikeize 3 Rikeize 3 is offline
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Location: N.C.
Join Date: Dec 2011
Posts: 9
Mein Auto: 2000 Z3
Originally Posted by FastWoman View Post
Hi all,

Some of you were so kind as to help me with a leak problem at the A*****ar seal on my 2001 Roadster. The possibility was raised that the rubber had shrunken and needed to be restored with Gummi-Phlege (sp?) or something similar. I did that, with only modest improvement in the situation. Then I followed another recommendation of tightening the roof latch. That apeared to "fix" the problem, at least for the moment.

Then I got my new/used hardtop and fitted it to the car. I got slow leaks at the A*****ar seals on both sides. This time, I KNEW that I had good, tight contact between the rubber on both sides, so the problem had to lie elsewhere.

When looking at the problem further, I discovered the problem. I'm thinking it's got to be a problem on other cars too -- probably even a common one.

If you look at the A-pillar seal on the windshield side, it looks like this...

See the almost triangular-shaped rubber recess in the middle of the thing? That's actually a rubber plug. Take note of it.

Now look at the top side of the seal. In this picture, notice the rain groove, just forward of the seal above the windshield. It communicates with a recess in the A*****ar rubber. An overflow (?) hole exists just next to it. You can put a probe in one hole and see it through the other hole...

These holes both connect to the interior of the weather stripping in the door jamb, such that water flowing into these holes flows around the door and exits through weep holes in the weather stripping in the step plate area...

(pardon the focus)

Now, look back up at the rubber semi-triangular plug. That's what stands between the convoluted aquaduct system and the A-pillar seal.

This is the other side of the A-pillar seal (on a hardtop)...

Note that if the water gets past the plug, there is nothing to keep it from flowing into the interior of the car. In fact it is actually diverted in that direction.


The glue/adhesive fastening the plug in the hole had given way, allowing the water to leak from the grand aquaduct, into the A-pillar seal, and ultimately into the interior of the car. I was able to verify that water came out from around the plug when I poured water through the drainage hole on the outside of the car. And yes, this had happened on both sides of the car. (Please note: I verified the leak before actually poking anything into this area!!)

Exploring further, I poked a screwdriver into the hole and found that the adhesive came apart VERY easily all the way around -- again, on both sides of the car. So I applied an adhesive to the gap between the plug and the surrounding rubber. It's curing tonight. I can only presume this will solve my leakage problem.

I *think* that may also solve the leakage problem of at least one other list member as well -- new ragtop, new leak. I think the leak can show up when a different amount of compression on the seal causes the gap between the plug and surrounding rubber to open up.

I hope that helps a few other folks!

As I had stated earlier in my first post. This fine persistent Bimmer member did her homework. I only hope Sarah aka Fastwoman is still around.
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