What is leaking here?

Q

q149

Member
Since I had my 2011 Z4, every now and then I notice something greasy leaking very slowly from the plastic interior parts right above the windscreen. Left side is worse than the right side. What you see on the pictures is from several weeks. Of course, usual suspects in this car for greasy leakage in the interior are the roof hydraulic lines. Except that my roof liner seems perfectly dry and there isn't anywhere in the interior where I can spot signs of hydraulic oil from the roof. Also this part of the car, right above the windscreen, simply has no hydraulic lines I guess? When I open the roof and watch from above, there is nothing in particular to see. Roof functions perfectly well so far.

Anybody who has seen something similar before?



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Ok, so i dropped the roof liner to have a look but no visual signs of hydraulic leaking. New pictures are from the right side which had the most greasy stuff slowly dripping alongside the interior plastic parts. There don't seem to be any hydraulics involved in the cowl panel locking system, if I'm not mistaken. Because that locking mechanism is the only moving part that could lead fluid into the windshield frame.

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There are no hydraulics up there

Unless there was some very weird pinhole leak spray fluid in that direction from way back
 
Could be a cocktail of water and glue/sealant from the windscreen.
 
Could it be from a blocked roof drain, so when the water is not draining it's mixing with grease from the catches and finding a way in the car , not sure if the A pillar has a drain or not , just a wilde guess
 
MikeyH said:
Silly question but what does it smell like?
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Indeed good question. Cause I had the honor to clean up and dry the battery compartment from a mixture of spilled roof hydraulic oil and water during my first week of ownership. So I know exactly what that stuff smells like and the boot still smells like it.

To answer it: not the typical smell from hydraulic fluid. But then it's only a very little amount. Anyhow, not noticing the typical smell in the interior.
 
Nick W said:
Could be a cocktail of water and glue/sealant from the windscreen.
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In fact the windscreen has been replaced about two years ago by the previous owner. Since I own it, it hasn't been in the wet except in the very beginning to check if I succeeded to make it rain proof.
 
q149 said:
In fact the windscreen has been replaced about two years ago by the previous owner. Since I own it, it hasn't been in the wet except in the very beginning to check if I succeeded to make it rain proof.
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Could it be the roof windscreen seal defective and letting in some rain / washing then slowly leaking through carrying some greasy residue?
 
Well that's actually a good point. That rubber seal has seen better times, small cracks can be seen due to aging especially when I push it a little. I don't know if it's worthwhile replacing it with a new one?

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MikeyH said:
Is it worth trying some gummi fledge first?
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This.
Give the rubber seals a good going over with silicone-based rubber care stuff (Gummi Pflege is a well known brand name but any will do the same job). It can work wonders in cleaning and softening rubber. It has cured a few 'weeps' on rubber seals for me.

My (wild) guess is it's water mixing with grease from the latches.
 
Looking at the last picture the glass fitment looks high.
Should be equal gap with the 2 vertical sides.
I know because i'm constantly washing seeds out of gap from a tree i have to park under.
Perhaps the sealant hasn't taken and driving airflow pushes water to the corners to leak in.
Looks sticky, is it washer fluid congealing.
 
Not a great pic, but see gap between rubber and glass at the top edge.
Doesn't touch the top rubber.
 

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flybobbie said:
Not a great pic, but see gap between rubber and glass at the top edge.
Doesn't touch the top rubber.
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I took another picture from the right angle this time. Now there seems to be a decent gap between rubber and top of the glass. Is it considerably larger at yours?

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