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DIY: Do It Yourself
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Old 01-10-2014, 06:32 PM   #41
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Don't give up after using the drain cleaner solution


I know this thread is a little old, but it helped me a lot so I thought I'd add my two-penneth!

The drain cleaner option worked well for me, Mr Muscle here in the UK.

Driver side took 5 mins, passenger side more stubborn at about 15 mins to clear. Flushed each side with about 10 litres of warm water afterwards.

That's not the whole story though. After doing that, and with it raining afterwards, I could see that the initial problem of water pooling near the drainage holes was sorted, but there was still a lot of water in the car after a drive!!

I removed the boot lining (not the sides - they weren't wet) and found a lot of water in the compartment for the tyre 'repair' kit, a few jug's worth! Took everything indoors and dried it for a day. Went for a drive, more water appeared, but without it raining. hmmm.

The only place left was within the lid of the boot itself (I think/hope). I'd removed the whole area where the tool box goes, but there must still of been a fair bit in there which was sloshing into the boot whilst driving, at least this was where it was coming through.

Conclusion (which may seem obvious)= Don't give up after using the drain cleaner solution just because you still get water in the boot. If you're like me you'll still have litres of water still sloshing around and it needs to come out, without all the boot interior still in place.

Go for a few drives. Keep mopping up, until finally no more appears.

But do remove all parts of the boot lining first, including the part in the lid itself (attached to the tool kit) - that's very important!!! Let them dry completely and don't replace them until there is no further sign of leakage in the boot.

Last edited by drdecker; 01-10-2014 at 06:42 PM.
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Old 03-21-2014, 05:10 PM   #42
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I saw this thread reference a hard top, do we have the same process/ issues for a soft top? [2000 323ci]
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Old 06-23-2014, 12:10 PM   #43
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I wish I had seen this thread before tackling the hydraulics of the soft top. Great DIY.

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Old 12-01-2014, 06:14 AM   #44
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Convertible top drainage issue. Battery compartment full of water. Spare tire area full of water. Rear carpet wet .
(At your own risk - This is not a recommendation or endorsement - at your own risk. But this worked for me.)

The Draino suggestion above worked for me! I was so PLEASED this worked!!!
I was about to go through the above detailed work to take my convertible top apart. When I saw a comment on this forum that the draino worked for that other person - but just the one liner. So I thought I would place more detail to help another guy/gal out. It was kinda cold outside and thought - it's a drainage hole. I'll be real careful pouring Draino (caustic) and not pour on paint or wires etc.

1) Get a bunch of towels/rags. Remove your battery and spare tire. You probably have 2-3 gallons of water sloshing around in there. If you don't dry this out - You will be fooled into thinking the draino didn't work. Take the rags - soak and squeeze water out of the towel and rags. Repeat as many times as you need to get most of the water dry in there. This is what took me longest amount of time. But a nice exercise for the forearms. Under the battery compartment took most of the time since there is small space to work rags into crevices. You have to work the rags into small crevices to get the rags to soak the water up. (I also removed my rear seat which is super easy in a E46 and left it by my radiator to dry properly overnight.)
2) Place a large bucket or plenty of newspaper to catch the Draino gel once the clog clears - wear gloves since it's a caustic if you go the newspaper route)
3) Open the top as per the instructions in the post. (Idea here is to get you clearance to the convertible top hinge/removal bolts area where they stupidly put inaccessible drainage holes. - Image 9 of the detailed post above)
4) I just poured 1/4 to 1/2 bottle of draino in each crevice (see image 9 of this post to get an idea of where draino goes) - waited 15-30 min and the draino started to flow from the bottom. (One side was less clogged so it cleared in 10 min. - the problematic side took 30-45 min)
5) (Don't pour the water until the draino flushes out from the bottom. The pool of draino at the top of the convertible top should no longer be there as it should have drained to the bottom and out the car to the ground). Took hot water (my tap is really HOT) and poured about 2 gallons of water on each side in the crevice (don't overflow -just enough to keep the crevice (image 9) continuously full of water. Pour slowly as you see the water draining below. Idea is to wash out all the draino out of the drainage hole.

(you pretty much - just follow the directions of the bottle except instead of a plumbing drain it's the drain for the convertible)

That's it - Saved me hours of work and now my battery, spare tire, rear seat and rear rug aren't like the neighborhood pool.
(I wonder if the local stealership does the same trick and charges $1000 for the work!)

Convertible top drainage issue. Battery compartment full of water. Spare tire area full of water. Rear carpet wet .
(At your own risk - This is not a recommendation or endorsement - at your own risk. But this worked for me.)

Last edited by 888treader888; 12-01-2014 at 06:36 AM.
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Old 12-01-2014, 12:42 PM   #45
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Put about a 1/4 cup of the draino. Give it 5-10 min, squirt a bit of hot water. I used a sports bottle for directional and volum control, I certainly didn't need this mixture over running the area into the trunk. It flowed right after. Jose down the underside where it drains onto the frame after capturing as much as possible- this will clean the driveway. Avoid Sending it to the storm drain.
Problem solved.
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Old 12-03-2014, 11:04 AM   #46
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I just came across this thread. I went to fit a new battery in my 330ci Convertible yesterday. I only have had the car a few days,

maybe I should have checked the spare wheel well before I bought it as it was full of water about 4" to 6" in it.

I have dried it out and now will try and unblock the drain holes given the information in this thread. Wish me Luck..!!
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Old 12-18-2014, 11:19 PM   #47
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Just used the draino method tonight. Poured half on each side, went played poker, when I returned mess on the floor. Rinsed and I'm happy now. Also happy I found out previous owner installed a dice aux input. Just bought the car, learning about it.

Last edited by Bonez2u; 12-18-2014 at 11:20 PM.
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Old 01-01-2016, 07:00 PM   #48
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Just did the draino method yesterday. Worked great!

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Old 02-03-2016, 01:12 PM   #49
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Does anybody know how this water gets in in the first place?
So if the seals are fine and you were only to put the roof down when it's dry, how does all this rain seem to run through the car like a river!
You'd think the drain holes were only meant for use if the hood is put down when it's wet.
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Old 04-15-2016, 10:11 AM   #50
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I just cleared mine. Last time I cleared was 5 years ago. Clogged with leaves and a piece of clear plastic film that is deteriorating from the inside of the top material. I see no need to unbolt the roof to do this if you can get access to compressed air and a nozzle, or a water hose with a good high pressure nozzle. I parked facing slightly down hill, then used liquid drain cleaner. After the drain cleaner flowed out, I ran water into the compartment until it was an inch deep. The water flowed out slowly. The drain cleaner helped because it partially dissolved the stuck leaves, but I'm not sure it is necessary. I used a coat hanger to reach the hole and clear it of debris. (Hanger works, but not near as slick as gregrr's machanism.) Photos above show where the drain hole is. You have to reach under the mounting bracket with the hanger. Then I sprayed with high pressure air and water until no more leaves came out. Now it flows as fast as the hose will run. As to why it fills with water, the gasket between the quarter panel and the top cover has drain holes apparently designed to drain directly into the top storage compartment above the hinge mechanism, visible in lower left side of image 03 at the start of this thread. I guess if all this fails, I would get the tools out.

Last edited by grubbab; 04-15-2016 at 10:27 AM.
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Old 09-06-2016, 10:48 PM   #51
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Tackled the drain holes this past weekend. Started with Draino. Cleared driver side in 5 minutes ( maybe not really too clogged) The Draino just sat there on the passenger side. It was getting dark so I decided to let it sit overnight. Next morning some had drained out. A little puddle on the paper, but I had hopes and went to work and let it sit. Came home and it all was still in there. I know caustic stuff sitting there, hated it. Anyway, not wanting to break the tools out yet, I tried gregrr's method with the brass pipe and weed eater line. Worked fantastically!

Tips: Study the pictures good to get a good ideal where the hole is located under the bracket.

Get the 5/32" brass tubing at a hobby shop. Google it, got mine 3 for $3.99 at hobby lobby. Good luck finding it while you are there, definitely ask someone. I tried to use 3/16" brake line at first, but was harder to bend and a little too big in diameter. Had the .8 or .08 weed eater line on hand.

Study the angle that gregrr goes in at.

Once you are pretty sure that you are in the drain hole, pull back on the brass rod on the same angle to make sure you are at the edge of the hole. My line had the tendency to angle out of the hole until I made sure I was at the back edge of it.

I bent my tubing with the end of a drill bit that was just a tad smaller than the tubing.

Anyways, thanks to all and hope your rear stays dry.

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Old 09-15-2016, 10:20 PM   #52
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This is really pretty straight forward to do.
TS Julia gave me a nice headache cause I decided to park nose high!!!
Did it solo!

-Marked the placement of the hinge on the bottom plate with a paint pen for alignment's sake
-Did one side at a time.
-Definitely have to take the top cover off!! (above rear arm rest)
-4 nuts...3 on the plate 1 on the front.
-2 wiring connectors to disconnect
-Driver side had the hydraulic lines...just unclip them from the box and sidepanel and just don't torque/pinch them.
-Had to muscle it a bit when aligning the hinge back on the mounting plate.

Just take your time!

Drain holes were obvious once the hinge was moved.
Compressed air was the key for me.
Chased the drain with some copper wire.

I would definitely NOT use Drano!!!

THANKS Fellas!!
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Old 09-21-2016, 08:17 AM   #53
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My rear seats are like a swimming pool at the moment, so I looked up this old post and I'm really glad that...

a) my post has survived the test of time
b) it has helped
c) others have improved it

Thanks for the image showing the location of the drain hole. This weekend I'm going to have a good prod around and maybe try the bent brass tube w/ weeder-wire trick.

I'm not so keen on pouring drain cleaner down the hole as I can see me making a right mess and melting the paint off

I've got the additional problem of having the hard-top on, but my son has said that he'll help me take that off. With any luck, the only blockage will be where the drain hole comes out along the sill.

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Old 09-30-2016, 02:01 PM   #54
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I have just cleared both the drain tubes and water still leaks into the cabin.

I think the cause is the sealant in the green circle has failed...

I've removed the sealant, used fibreglass to seal the area and the leak seams to have stopped.

I'll confirm if the repair has worked and post an image of the repair later.
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Old 12-31-2016, 10:21 PM   #55
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So first, thanks to the OP for this DIY!!! After some big rains, my passenger side rear seat floor was all wet. So I started googling and asking on forums about drains and what might cause this, and one of the places it led was this DIY. First I pulled the rear seat bottom out and shoved some towels down under the carpet to absorb the water, and dumped some deodorizer down there (Natures Miracle. Smelled like something died in the car from the moisture). And then I finished drying the carpet out by putting a fan on it for a few hours.

So the other day I started by pulling the front door panel, suspecting the vapor barrier caused the issue (since I once had that window broken and replaced). But the vapor barrier seemed very well sealed. So, I opened the top well and tested both drains, and the driver side drained quick, but the passenger side drained very slow and there was standing water sitting there. After my test, the passenger rear carpet was wet again! So I decided the clogged convertible top well drain was the cause.

I followed this DIY and cleared the drains with compressed air, and chased them with copper wire. After that, the passenger drain cleared quickly and made the sucking sound of a clear drain!

After all this, my contribution is -- don't do the drano method!!! For me, the water ended up in the passenger compartment, the last place you want drano! I also pulled up the green sound proofing under the seat bottom and found water there, so unless you want to risk drano under your seat and carpet, I would avoid the drano method!

Following this DIY took some time, but it is actually pretty easy (but once the top is unbolted, you should have an assistant to lift it, while you clear the drains).
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Old 03-22-2017, 11:44 AM   #56
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Hi there, Well there was no way I was in the mood to disassemble the whole backseat. When you partially open the convertible top, the drain holes are under the hinge; you cannot see them, nore find them to floss the gunk in any way. Solution I used was draino. put it into the cupped area where the water puddles, let it sit for a bit, I waited about 10 minutes. One side cleared, the other was stubborn, so I put warm water in it (draino is dangerous stuff) and boom it started flowing. Then flush with plenty of warm water, then hose off underneath so that is doesn't remove paint.
I tried this again a few years later and is was more stubborn.... make sure those tubes are rinsed well to avoid corrosion of any kind and possible later problems.
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Old 04-08-2017, 05:07 PM   #57
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I just used the 5/32 brass tube with a bend in the end today to go underneath the bracket. Once the tip was in the hole, it was almost unnecessary to even push the nylon line through to snake the hole, the water drained out like a flushing toilet!

Any method that doesn't require me to remove parts from the car is a method I will always try first.

IMO, try the brass tubing/clothes hanger method before involving anything lol

Last edited by 2000e46vert; 04-08-2017 at 11:43 PM.
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Old 11-02-2017, 06:18 PM   #58
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Hey y'all--

So when you get water in your rear floor and you look inside the top storage compartment, do you immediately say "No wonder the drain's clogged, look at all those leaves/pine needles/mouse nests in the compartment?" Cuz I know mine looks clean...

Got a wet backseat floor for the first time this past weekend in a LONG heavy rain....

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Old 12-05-2019, 08:25 PM   #59
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Maybe a quicker Better Way

My hat's off to all of you that got out your DIY tools and followed the posted procedure, but for me I believe I've found a easier less time consuming fix. At least for me it worked and no tools are needed.

First off this may not work in every case, but if all of a sudden after a rain you have a wet truck this may do the trick.

Here is what I did.
1. Operate the top so that the top storage compartment is assess-able.
2. Carefully pour enough "Draino" into the area or areas where the top
mounting brackets are bolted to the body. Do not pour the "Draino" directly
on the mounts.
3. Wait thirty (3) minutes. Inspect the area of the mounts to see that the
"Draino" has drained into the drain tube.
4. Pour hot water slowly into the mount area.
5. Shortly water should drain in front of the rear tire about six inches in front of
the front edge of the real wheel well.

Additionally on my "05" at lease there is a double chambered funnel like rubber seal. At lease it appears to be a seal. It actually drains water into the top compartment that collects in the top mount area that is drained away through the drains provided.

The design of the mount area leads me to believe that that water is intentionally allowed to drain into this area and is drained away by the drains.

Finally I recommend periodically inspecting the top compartment mount area for water, as I believe when the car is washed or is parked in the rain that this area will always be wet, but if there is any appreciable water under the mounts the drains should be cleaned.


Last edited by Warbird5; 12-05-2019 at 08:49 PM. Reason: Spelling and addition of needed words.
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convertible, drain, e46, hole

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