The roof leak saga

[yellowjacket]

Hello all - My Z3 came with about 180k miles and a roof leak which left the (right hand) passenger seat filled with water after a rain. I GummiPhledged and more importantly sealed the top of the A-pillars (wit Sugru--great stuff) and the seat no longer fills up, but water is still getting in. Using the tried-and-true paper towel test, I find the water is coming in on the right hand side between the seat and the door, toward the back of the seat. In other words, it is either entering about midway on the window or traveling down from the A-pillar area and dropping there. (see exhibit 1). While the water accumulates behind the right hand seat, it doesn't seem to be entering anywhere else.

I wonder about two things: One, the window on the door rides high above the frame piece (see exhibit 2), unlike the (nonleaking) left hand door. Could this be allowing a gap, or disrupting the usual drainage? Should troubleshooting include lowering the window position?

I've syringe-checked the drain in the A-pillar and was rewarded with a puddle, but wonder whether a more thorough drain cleaning would help, as well.

Thanks in advance for your thoughts on this, folks.

 

[Ianmc]

I would get the glass window fitted properly first.

 

[Dino D]

I had a leak round there and it was the membrane in the door itself, came loose. Pop the door card off and have a look if it’s still making a good deal.

 

[Bumpa]

Same as Dino. The leak on mine was from inside the door because the plastic membrane was damaged allowing the water that is normally present in the door to run out the bottom inside the car. I ended up making a completely new and larger plastic membrane and have had no more trouble.

 

[yellowjacket]

Thanks for your input, guys. Ian, good point. Sometimes it takes writing something down before you notice how obvious the solution is. So I tried lowering the window to the height of the top of the frame, thinking that it had been pushing up the rubber seal (since it seemed way too high). However, with the window lowered to the height of the top of the frame, there was an obvious gap (picture below)--in other words, PO had probably adjusted the window high to seal the gap.

Dino and Bumpa, the door definitely has problems. The windows works intermittently, maybe from the wet, and is going to need disassembly at some point. However (and I apologize for not mentioning this in my first post), there's a regular drip that develops under the roof inside the window which may have something to do with it (bottom pic below).

I'd assumed the leak is a result of water channeling not working. The tops of the A-pillars are sealed, but maybe the drain isn't working, or the water is getting in at the aforementioned gap between the top of the window frame and the roof. Maybe some carefully applied Sugru to fill that 5 mm gap is worth a try.

 

[the Nefyn cat]

Something doesn't look right in the picture of the outside, just been out to look at mine (which doesn't leak, how I love to tempt fate) and if I get time tomorrow in daylight I'll stick a picture on here. Your roof doesn't seem as far forwards as mine, if you see what I mean, and the latches do have a bit of adjustment on them.

 

[yellowjacket]

Interesting. So perhaps a combination of latch and window adjustment would do the trick . . . .

 

[the Nefyn cat]

I realise it's probably not much help to you, but this is how my one sits, and, I'll say again, it don't leak. If yours has been left adjusted too high for a long time maybe the rubber seal has moved a bit to fit the window, and may re-adjust itself given a bit of time. Or not.

 

[yellowjacket]

Thank you, Cat. I'll compare you pic (of a wet Z!) to mine when I get back to it IRL tomorrow. I'm esp. interested in the latch adjustment possibility, maybe followed by some window height tinkering.

 

[the Nefyn cat]

If I remember rightly, there's also an in-out adjustment somewhere inside the door which moves the top of the window in or out a bit, not had to do it on mine, but I'm sure I read about it on here somewhere. If I'm wrong I'm sure someone will say so.

 

[roadvoyager1]

If I remember rightly, there's also an in-out adjustment somewhere inside the door which moves the top of the window in or out a bit, not had to do it on mine, but I'm sure I read about it on here somewhere. If I'm wrong I'm sure someone will say so.

The are a couple of bolts on the underside of the door which can be loosened and allow the angle of the glass runner to be changed. Before you start put reference marks on the door snd bolts so you can return them to the start condition. Be careful as changing the angle will compress a different area on the seals and lift an area that was previously okay! I had a small leak on the top seal and adjusted the top of the window inwards. This cured that leak but lifted the glass from the mid section of the A pillar. Took several attempts to get the angle just right so that both seals we doing their job.
There are also small drain holes on the front corners of the A pullar seals. Use a long tie wrap to make sure they are clear.

 

[yellowjacket]

Thanks--this is clearly put and sounds do-able. Did this involve removing the doors or putting the car on a lift?

 

[the Nefyn cat]

No need to take the doors off, or lift the car up. The card should come off easily, just a screw behind the window switch (prise the switch out, you'll find it) and then the normal easy-break plastic stud things to lever out. Don't forget there's a whole bunch of wires hiding behind there.

 

[yellowjacket]

That's all I needed to hear. The combined advice here is very encouraging. Will attempt and report back!