mels545

After a rain shower I found this water puddle on the battery hold down brace. I couldn't trace where it came from but don't think it would come from the SR drain this high up. Could the water be leaking around the tail light? Is it difficult to remove the light? I also found a drop below the rectangular trunk vent in batt compartment. Is this supposed to be sealed. It feels a little loose on the bottom.

neil.d

Hi

Its a common issue that can cost thousands if undetected.

Have a look at this post.

http://forum.bmw5.co.uk/viewtopic.php?f=12&t=68452

3 months on and I have no water at all in my compartment - touch wood.

Initially My battery was sitting in an inch of water and my spare wheel well had a good cupfull.

Neil.D

mels545

Thanks Neil I reviewed the tread. It this the same drain location for the sedan? I can't understand how the water would end up on top of the battery? It seems like it's running down the back from around the tail light area.

neil.d

Hi, yes saloon (sedan) and touring (wagon) operate on the same principle.

When I first found the problem I thought it was coming from the quarter window it was so high up.

The blockage backs up and eventually floods the tubes and runners.

mels545

But how would get on top of the battery hold down strap unless the water was 6 inches deep!

neil.d

If you see where the tubes come from and what they do you'll see.

The ends block up and the water backs up, eventually leaking into the tube housings.

They leak down from the roof, onto the felt trim, battery strap, battery void and spare wheel well - killing the electrics.

If youre smart you'll follow the insructions, soak up the moisture and keep an eye on the water.

After 3 months mine is now bone dry - touching wood.

If youre unconvinced, open the sunroof and pour water into the runners. Watch it drip out by the back wheels. Then after the proceedure it will pour.

This is of course having already wrapped the modules in the wheel well in some sort of waterproofing.

neil.d

Oh and sorry not to have answered your question.

The water is just pooling there. It runs down the sound proofing felt or drips to that location.

mels545

Thanks for all the input.....On the Sedan there is no sound proofing material along the walls of the trunk (least not in mine). Only on the top of the wheel well and that's dry. I'll remove the fuse holders on that side tomorrow and look for that tube. But I still can't understand how the water will flow uphill and collect on the top of the battery hold down? It's got to be a trunk seal leak or leak from the tail light and running down back wall onto the hold down which is at least 5 inches from the compartment floor.

mels545

I found that the water was running down the back of the wheel well, behind the fuse panel, and along side the re-mounted electric modules that I moved from under the spare tire. In the sedan the sunroof drains can only be accessed by removing the rear wheel well liner. There's about 10-8mm screws and 2-10mm plastic nuts holding it in place. Once inside, I found this drain flapper valve attached in the upper back area of the well. As can be seen in the picture the 4 flapper portions have been sealed together by scale and dirt preventing any water from flowing through. This has been the cause of thousands of dollars of flood related repairs. I took a pair of dykes and snipped off about 1/8 inch of each flapper arm to prevent further plugging. I suggest that even if you don't have a flooding problem that you have these flappers removed or modified as a preventative measure.