E93 water in battery tray

NoQuarter

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Nov 24, 2017
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E93 (Convertible) With water in battery tray

We have an E93 that began having a starting problem and we found the battery tray full of water.
The cable to the starter had corroded so bad it broke off as soon as we moved it around.

With the cable fixed, any thoughts on where this much water comes in? I don't know this car very well and just hoping this is common knowledge with the convertible owners. Searching in BMW forums for leak info can be exhausting!

We are drilling holes in the tray to allow future water to drain but slowing it down a bit would be nice. The padding above the wheel arch is damp so it seems it is coming from above - so trunk seal or something more difficult like the convertible top seals?
 

aus335iguy

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Nov 18, 2017
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Ive seen a correlation with aftermarket tail lights and leaks into that area but nothing in the area you’re talking about.
 

doublespaces

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Oct 18, 2016
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That sounds like a convertible top or trunk issue with the seals. Sometimes the hinges can be off a bit. Pressure washing too hard in some areas is something to consider also. Ive seen water leak in by my windows sometimes if I spray too much at the top.
 

noshi

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Apr 25, 2018
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E90 335i
I encountered the same thing once chasing a no start. Same exact scenario except an e92. In this case it was coming in from the tail light area. If I remember correctly its a rubber grommet that was dangling. Havent dealt with e93's those trunk areas are a bit different.

Definitely get it situated, with the owner I was helping theirs was so bad the water drained itself out since the metal rusted away and created a nice size whole. Surprised the battery stayed in the car.
 

doublespaces

General of the Army
Oct 18, 2016
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If you have PDC or the trailer hitch, there is a rubber grommet back there. You have to pull the battery out in order to really get access to it. There is another one for other wires, I think its related to comfort access, etc.

Outside right rear:
upload_2018-5-25_12-44-15.png


Battery area with tray removed:
upload_2018-5-25_12-44-35.png
 

NoQuarter

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Nov 24, 2017
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Great pics. Thanks.

We pulled one of the plastic hole plugs below the battery tray so now water will drain.

The water is coming in from the tail ligjt area. Runs along the gutter from the trunk lid/hinge area, hits the tailight then come in around the body seams in the battery area.

Now we just need to figure out best way to seal it up.