[Tommy D]

I have been asking questions over at the Bimmerfest Fseries forum and it seems dead over there. Not like the E46 forums.
I found this site today and it looks like a lot more active.

So has anyone experienced water getting in the battery area? I just picked up a F36 last month and wanted to check the date on the battery and with the current rain the foam and controls boxes we're all wet. Not a good thing.
Is this a sunroof drain issue? The weather stripping on the hatch and drain channels along the side are clear. The wetness seems to be all the way up near the back window as the foam was soaked. I didn't see any issues with the weatherstripping at the top of the hatch either.
It's going in the shop in a week, but curious if anyone has any ideas.


Thanks.

*Update*
Sunroof drain was the issue. It's all sorted, thanks for all the help.

[alexonahurry]

Originally Posted by Tommy D

I have been asking questions over at the Bimmerfest Fseries forum and it seems dead over there. Not like the E46 forums.
I found this site today and it looks like a lot more active.

So has anyone experienced water getting in the battery area? I just picked up a F36 last month and wanted to check the date on the battery and with the current rain the foam and controls boxes we're all wet. Not a good thing.
Is this a sunroof drain issue? The weather stripping on the hatch and drain channels along the side are clear. The wetness seems to be all the way up near the back window as the foam was soaked. I didn't see any issues with the weatherstripping at the top of the hatch either.
It's going in the shop in a week, but curious if anyone has any ideas.


Thanks.

Have heard this before and it was the rear light sealings - between body and light. BMW seals are notorious to fail. Not sure if that's the reason but would give it a shot and drain water over it.

[Tommy D]

Thanks Alex,
I looked at it again and the wetness is far up into the body toward the rear window glass. I was able to reach my hand up and the foam between the hatch strut and inner quarter panel is soaked and the black insulation is also wet. I suspect the rear quarter window seal is the issue? Can it leak here? It looks like someone had the trim off at one time and doesn't seems clipped in properly.
Does anyone know if there is a sunroof drain in this area or only along the A-pillar?
I was able to get the car out of the rain till it goes into the shop next week as they are usually slammed and I have to wait 2-3 weeks for an appt when you contact them.

*UPDATE*
I remove the trunk inner liner on that side and determined there is no sunroof drains. So I am fairly certain it is the rear window seal. I will have it confirmed by the garage and have it replaced.

[montr]

I had water in the battery tray in my E90. The E90 sunroof has four drain tubes, one at each corner. The car was parked outside facing the house, with an incline toward the back of the car. I had to pull partially the back of the inside roof liner to access the drain tube. I was able to fix the blocking by using the string of a garden edge trimmer and compressed air.

The F36 has 4 drain hoses shown by the 4 arrows below

[Tommy D]

montr,
thanks for the info. I'll see if I have time to remove the headliner to access the drain tube before my appt. Any trick to see the drain at the sunroof end? I have the sunroof open all the way and don't see it.

[montr]

Originally Posted by Tommy D

montr,
thanks for the info. I'll see if I have time to remove the headliner to access the drain tube before my appt. Any trick to see the drain at the sunroof end? I have the sunroof open all the way and don't see it.

It is almost impossible to see the drain tube from an open sunroof. That is why I had to remove part of the headliner. The sunroof two back drain tubes exit behind the rear fender. To access, you have to pull the carpet trim just above the battery. The other tube is at the same location on the opposite side. Only way to get to the the tube end is from the trunk. On my E90, I was able to pull it back to unplug and push it back.

You can test if the drain tubes are working properly by parking in incline (forward and backward) and pouring slowly water in the left and right sunroof channel. You should water falling behind the front tires and at the back of the rear tires. If you decide to pull the back of the headliner, send me a private message, I will try to send you more detailed instructions.

This is not the correct car but it will give you an idea of where the two back drain tube are located:

[Charles B]

My old E46 had this. The sunroof rear drains became disconnected.

[Tommy D]

Ok, another question, if the sunroof is fully closed and sealed, how is water getting into the sunroof to drain?

[montr]

The sunroof seal, even when closed, is not perfect, there are still some water that can still get in. The 4 drain tubes will take care of it.

[Tommy D]

Ok, update on my leak. Got the car back from the shop today.
The sunroof drain in the back disconnected from the pan as Charles B had on his car. Thanks Montr, you were indeed right. The mechanic told me the drains sometimes disconnect from having the roof open at highway speeds, so it was like this from the previous owner. I am glad I found it when I did.
Fixed for free.

[MidtownMike]

Aw man, can't have my sunroof open on the highway? Wtf? Aren't there any hose clamps to keep the drain hoses in place?

[montr]

Originally Posted by MidtownMike

Aw man, can't have my sunroof open on the highway? Wtf? Aren't there any hose clamps to keep the drain hoses in place?

No hose clamps. Hoses are held to the sunroof cassette by friction only

[Tommy D]

It rained last night, and I checked the same area today and it's wet again, time to go back to shop next week to find out what it is this time. I am really regretting this purchase, I bought someone else's problems.

[montr]

Originally Posted by Tommy D

It rained last night, and I checked the same area today and it's wet again, time to go back to shop next week to find out what it is this time. I am really regretting this purchase, I bought someone else's problems.

It is easy to check if the drain tube are working properly. The two front tubes are visible with the sunroof open. With a small water can (or other similar arrangement), you pour water on each side of the sunroof cassette and you should see water on the ground behind each front wheels. Next, you park on an incline or jack the front of the car. You pour water on each side of the sunroof cassette and you should see water on the ground in behind the rear wheels.

If one of the drain tube in the back was disconnected, there should have checked if is blocked (they sometime get block from the grease of the sunroof mechanism). It can be unblocked by using an air compressor (I used air and a string from a garden edge trimmer).