Fixing Trunk Leak?

[Johno]

My 1989 325IS is leaking into both wells of the trunk.

I replaced the tail light gaskets and the trunk seal, and confirmed the sunroof drains are unpluggged and not leaking.

After a couple of days of rain my hopes of solving it were dashed.

I have no idea where the battery well water is coming in from.

On the driver side I peeled back the trunk mat and saw a nice puddle up high, on the intersection of the trunk and the well on the driver side.

There is seam there on the far left side of the trunk floor that is very wet. Apparently there is a seam hidden by the bumper that is open and channeling water into the trunk.

Anybody seen this one before?

How hard is it to remove the bumper to access the body sheet metal under there?

Because it is in a hidden area I plan to clean it up good and maybe even apply tar or something robust to that seam to stop this nonsense.

How do I find where the battery water is coming from?

thanks

[Bison Dele]

Hey man,
I had a similar issue. Everytime it rained water was leaking into the trunk. It turned out water was leaking in from the rear light that sits on top of the trunk lid. The seal on the screws/screw holes was allowing water in. I applied sealant to the screws and replaced them, and it fixed the issue. If you have the same light, its worth taking a look.
Good luck.

[Strelok]

Take a look at your antenna grommet as well. Only other place I can think of.

[Johno]

Hey man,
It turned out water was leaking in from the rear light that sits on top of the trunk lid. The seal on the screws/screw holes was allowing water in.

Thanks -- I am not sure what you mean by a light on top of the trunk.

I don;t recall ever seeing this.

My driver's leak seems to be clearly coming in through a seam a few inches below the tail ight, where the trunk floor meets with the sheet metal below the tail light. There is practically a puddle standing there, soaking the trunk mat.

The question is how hard it is to fill and seal that seam from the outside.

Is bumper removal difficult? Reinstallation easy or hard?

I believe once I can access that space on the outside of the car I can clean and seal it from there. I hope.

Take a look at your antenna grommet as well. Only other place I can think of.

Thanks. That is seeming to hold water fine.

[DaRvDrUmS]

Replace the antenna grommet, tail light gaskets, and trunk gasket...you should be good to go! Do a search too, the water in the trunk issue is pretty common with e30s. Good luck!

[e30Champ]

I had the same problem with my 1987 325e. My leaking was coming from around the taillight gasket. I know you said you replaced those, but try to really crank the nuts that hold it in place down. That solved it for me. Under the battery there is a drain plug which used to hold a little reservoir for pumping fluid into the old school batteries. Try taking out your battery and the little platform under it to see if that drain plug is open, or if the little reservoir is still there (may still have fluid in it). Not too helpful, I know, but perhaps this can help steer you towards finding the problem. Good luck!

[Johno]

Thanks for the help. I did a search on trunk leak and found a few threads.

The tail light gaskets are tight, cranked down to the max.

I can see a wet seam inside the trunk with water puddled beneath it.

On the driver side that is the (a) source for sure. It is not running down from the tail lights It is coming directly through the rear of the car, apparently.

[russo7]

drill a decent sized hole in both of the wells, then dry the wells with a shop vac, or heat gun, spray the holes to protect from rust, take all the carpet out, remove the tar, sand the surface rust away, spray paint it for protection, and call it good.

[paxmaster2000]

i am having the same problem . did everything you listed . still am collecting water on the battery side. everytime i think i will be able rip into it gets cold.

[ivanandrade]

You dont have to drill holes in the wells, because there are the factory holes already there, all you have to do is used a small screwdriver & unplug them.this holes are not easy to find. one of them is directly under the jack. also the light lenses themselves get separeted forming a crack between the front & back of lens, this is also one of the places that the water gets in. Never drill any holes in your bimmer.

[Johno]

After looking more and reading some other trheads under "water in trunk" I found two of the six bolts missing that are supposed to hold on the rear wing.

With my daughter in the trounk and a bucket of water she was able to see water dripping in through the holes.

I gots some 3M adhesive trim/gasket goo and made a thin bead around each hole in the trunk lid, and bolted it dow.

Now -- I have a damp rear seat floor carpet on the driver side. It is mildewey.

Could water be getting there all the way form the trunk lid, or is there more investiugating in my future?

Where will water come in to the rear pass floor carpet?

Thanks,

[russo7]

Never drill any holes in your bimmer.

shut up

[5percentEuro]

I'm having the same problems with my 318i. I get water int he trunk after rain as well as moist carpet in the rear floorboards. Also after a touchless carwash, I can see soap drip in from the air return in the passenger floor board? Help us


Sent from my iPhone using Tapatalk

[i_am_ed]

Another leak source is the body attachments that go behind the rear windows/doors. They are only held onto the body with plastic grommets. The leak in my coupe was falling onto the rear wheel well, so it was going forward or backward depending on how the car sat. Easy fix, hard to find, reinforce with silicone.

http://www.realoem.com/bmw/showparts...30&hg=51&fg=20

3 is held on by 3x 18, each side. I believe 18 has 20 attached.

HTH

[Johno]

Another leak source is the body attachments that go behind the rear windows/doors. They are only held onto the body with plastic grommets. The leak in my coupe was falling onto the rear wheel well, so it was going forward or backward depending on how the car sat. Easy fix, hard to find, reinforce with silicone.

http://www.realoem.com/bmw/showparts...30&hg=51&fg=20

3 is held on by 3x 18, each side. I believe 18 has 20 attached.

HTH

After a week away no water in the trunk. Those missing bolts in the rear wing are now solved.

Now onto the damp floorboard with mold on the pass. side.

Thanks for the post ab out the window leak. How do we access 3/18/20?

Are the 18 and 20 parts the one that are leaking into the pass floorboard?

Thanks

[5percentEuro]

Another leak source is the body attachments that go behind the rear windows/doors. They are only held onto the body with plastic grommets. The leak in

After a week away no water in the trunk. Those missing bolts in the rear wing are now solved.

Now onto the damp floorboard with mold on the pass. side.

Thanks for the post ab out the window leak. How do we access 3/18/20?

Are the 18 and 20 parts the one that are leaking into the pass floorboard?

Thanks

Floorboard issue is due to a drain behind the side skirts filling up and running into the carpet well. I'll look to find the thread on r3v. It was fixed by drilling two holes under the side skirt drains


Sent from my iPhone using Tapatalk

[hobbes567]

You'll probably need to pull the carpet out to get it to dry completely. It's not a terrible job, I did it in about an hour and I've never done it before. I pulled mine out because there was a gelatinous ooze coming out of my drivers footwell carpets. Thats how wet they were, and they have been that way for god knows how long. The carpets went straight to the garbage. Now, I have to fix leaks and find new carpet

[Johno]

Floorboard issue is due to a drain behind the side skirts filling up and running into the carpet well. I'll look to find the thread on r3v. It was fixed by drilling two holes under the side skirt drains


Sent from my iPhone using Tapatalk

Thanks

Look forward to it.

I am so new to the car I am not sure what the "side skirts" are.

[Johno]

Turns out I STILL have a leak into both trunk wells/. I thought I got it for sure with fixing the rear spoiler leak.

I can our water all over the trunk and splash it into the wheel wells and my daughter inside can not find a leak.

I looked in there after a heavy rain and saw nothing. After driving in water last night there is water in both sides.

please help. this is so frustrating.

[Mamatried]

Another leak source is the body attachments that go behind the rear windows/doors. They are only held onto the body with plastic grommets. The leak in my coupe was falling onto the rear wheel well, so it was going forward or backward depending on how the car sat. Easy fix, hard to find, reinforce with silicone.

http://www.realoem.com/bmw/showparts...30&hg=51&fg=20

3 is held on by 3x 18, each side. I believe 18 has 20 attached.

HTH

Hi guys....yes I know, resurrecting this ancient thread. I believe my battery well leak in my 91 325i coupe is from this molding on the C-pillar mentioned by i_am_ed in this fossilized post from 2010.

My question is, how does one remove this piece of trim? Nothing obvious from looking at it and pulling gently on it.

Thanks!

Andy

[jmorgan456]

Hi guys....yes I know, resurrecting this ancient thread. I believe my battery well leak in my 91 325i coupe is from this molding on the C-pillar mentioned by i_am_ed in this fossilized post from 2010.

My question is, how does one remove this piece of trim? Nothing obvious from looking at it and pulling gently on it.

Thanks!

Andy

I just bought an E30 project car. It appears I have the same leak. No obvious way to remove that trim...
How did the posters do it?

[82eye]

I just bought an E30 project car. It appears I have the same leak. No obvious way to remove that trim...
How did the posters do it?

they probably didn't figure it. remove the clip on the drain rail trim or slide it toward the front of the car. be careful, i waited two years to get a replacement, and they are different side to side. then you can remove the back vent wing with the trim included. grip it from the back and carefully pull toward the front of the car. it will pop off intact. replacing the plastic mounts often will get rid of leaking.