Water in foot-well – the cure.

UK forum for general and technical discussion about the Z3 roadster

Moderator: Gazza

Post Reply
Del
Joined: Sat 19 Nov, 2011 18:35
Posts: 2115

  Z3 roadster 1.9

Water in foot-well – the cure.

Post by Del » Sat 08 Nov, 2014 18:46

We have had some torrential rain down here in Somerset during the past 24-hours and this morning the Z3 had a puddle in the passenger foot-well. We are well versed in the usual roof, door and boot leaks and all those areas were dry. A clue was that the car has been a little hesitant in starting the last couple of days in the very wet weather and when the heater fan was turned on this morning there was a “sloshing” noise coming from the fan.

We suspected that rainwater was going through the heater fan vent in front of the windscreen and not draining away properly. After searching the internet this seems to be a general E36 problem and not something specific to the “soft-top” Z3.

See attached link http://www.bimmerforums.co.uk/forum/f92 ... ns-t32501/

The Z3 was slightly different from the E36 described in the above.

1. Remove the wiper arms – takes seconds with a small puller, otherwise quite tricky to do.

2. There are 8 little square “push-in” tabs holding the plastic cover on. These are in two parts and you need to prize out the centre part first.

3. Pull off the rubber sealing strip that runs along the front edge.

4. Carefully pull away the plastic cover ensuring that you have a finger on the back of the remaining tab portion still in the cover, so that it does not fly off into the engine bay when being “unplugged”.

5. You then have clear access and vision to the heater fan cavity behind – mine still had a “puddle” of water inside. Towards the middle there are two flexible, rubber “grommet drains” which on my car were completely blocked with 16-years of silt. These appear to guide rainwater down a spout to run harmlessly down the side of the bell-housing. The grommets can be pulled out from inside the heater fan cavity, cleaned and the cavity flushed out.

6. There is a strip of flexible black mastic running between the bottom of the windscreen and underside of the plastic cover – we renewed this with some similar black building mastic which can be used in wet conditions.

What seems to happen is that these “grommet drains” gradually block over time causing the water level in the heater fan cavity to rise so that water can enter the fan to get dispersed in the plastic heater piping in the foot-wells. For some reason the passenger side (RHD cars) seems to be the first to get the problem. The problem is that this is the area where both the ECU and alarm module are situated and it seems that the moisture produced can actually cause hesitancy in starting as well as condensation in the heater system generally.

Having done a subsequent search on this forum there are numerous reports of “puddles in the foot-wells” which may be caused by this known E36/Z3 issue.

I hope this may help other forum members suffering the same problem in the current wet weather.

Brian4
Joined: Mon 19 Dec, 2011 19:02
Posts: 534

  Z3 roadster 3.0i
Location: Hinckley

Re: Water in foot-well – the cure.

Post by Brian4 » Sat 08 Nov, 2014 19:01

This is quite a well known issue with z3 and has been mentioned a few times. Seems to be quite common on BM's in general as the E61 5 series was known to have this issue and some of the electronic modules were in the hole and were known to flood.

Agreed now it is getting to winter and rainy season the front scuttle panel on all Z3s should be removed and this are cleaned out and the 2 elephant trunks cleaned out. For how long it takes I do ours Autumn and Spring along with clean out the arch liners and the hood drains.
Brian
3.0I Topaz Blue


2000 E36/7 Z3 3.0i
2016 F31 335d
2015 F21 118i

Del
Joined: Sat 19 Nov, 2011 18:35
Posts: 2115

  Z3 roadster 1.9

Re: Water in foot-well – the cure.

Post by Del » Sat 08 Nov, 2014 20:45

They seem to be called "scuttle drains" :D

Image

Cooper01
Joined: Tue 29 Apr, 2014 09:06
Posts: 152

  Z3 roadster 3.0i

Re: Water in foot-well – the cure.

Post by Cooper01 » Tue 11 Nov, 2014 13:21

Excellent write up. Thanks.

Vic-Z3
Joined: Fri 11 Jun, 2010 20:28
Posts: 915

  Z3 roadster 2.2i
Location: Redditch
Contact:

Re: Water in foot-well – the cure.

Post by Vic-Z3 » Thu 13 Nov, 2014 19:22

It is certainly one cure ............... :|
----------------- BMW Z3 Das Beste Auto -----------------

Mein altes Auto riecht nach Nudeln, hat dieses Auto eine Wurst Geruch.

ualla
Joined: Mon 10 Feb, 2014 16:37
Posts: 89

  Z3 roadster 2.0

Re: Water in foot-well – the cure.

Post by ualla » Sat 29 Nov, 2014 16:25

Hi guys, quick question about this solution.

This morning I noticed that I had a little lake in the passenger foot-well and am trying to understand whether the problem is where the soft top meets the windscreen or whether it is because of the problem mentioned in this post. If it is water coming through the fan, will the carpet at the end of the foot-well (where the engine bay is) be wet as well? That part of my carpet is dry, only the floor of the foot-well is wet.

Thanks!

Brian4
Joined: Mon 19 Dec, 2011 19:02
Posts: 534

  Z3 roadster 3.0i
Location: Hinckley

Re: Water in foot-well – the cure.

Post by Brian4 » Sat 29 Nov, 2014 20:19

Water in the footwell can come from 4 main places
1 as in the first post
2 from where the roof meets the top of windscreen.
3 from poor seal of the membrane behind the door cars as ours did.
4 the roof drains where the door meets the rear wing.

There is approx 2" of foam under the carpets so if the carpet has a puddle there is a lot of water under them and the water seems to run under the carpets rather than on top. I would check the drains first then spray a hose on the side window with the door open and see if any runs out between the door card and door and then check the roof seals.
Brian
3.0I Topaz Blue


2000 E36/7 Z3 3.0i
2016 F31 335d
2015 F21 118i

ualla
Joined: Mon 10 Feb, 2014 16:37
Posts: 89

  Z3 roadster 2.0

Re: Water in foot-well – the cure.

Post by ualla » Tue 02 Dec, 2014 12:22

Thanks Brian, very useful.

Upon further inspection, I noticed that I have water under both passenger and driver seats. I'm thinking it might be because of the drains. Do you by any chance have a picture of where exactly the drains are? Just so I can check whether they are blocked or not...

Also, I'm not sure I fully understand your third point. How did the water get in behind the door cards?

I'm going to have to take the seats out of the car to dry everything, this is going to be a nightmare :head:

Brian4
Joined: Mon 19 Dec, 2011 19:02
Posts: 534

  Z3 roadster 3.0i
Location: Hinckley

Re: Water in foot-well – the cure.

Post by Brian4 » Tue 02 Dec, 2014 17:03

Hi Uella
When it rains some water always finds it's way past the seal between the door glass and the rubber seal and runs out the drain holes at the bottom of the door. It may not be very much and this then drips off the bottom of the glass and some ends up on the membrane. On the Z3 this is fixed to the door with butyl sealer. On ours the bottom had either never been sealed properly or had been pulled away in the past and now wasn't fixed and allowed water to drip out and into the car.

I resealed our's with silicone and not had a leak since and the car is out all year.and this was 2.5 years ago

Image


Here's a picture of the amount of foam under the carpet.

Image

I will get some pictures of the drains in the engine bay at the weekend if you can wait.
Brian
Brian
3.0I Topaz Blue


2000 E36/7 Z3 3.0i
2016 F31 335d
2015 F21 118i

ualla
Joined: Mon 10 Feb, 2014 16:37
Posts: 89

  Z3 roadster 2.0

Re: Water in foot-well – the cure.

Post by ualla » Tue 02 Dec, 2014 17:22

Thanks Brian! I can most certainly wait until the weekend, really appreciate your help. I'll have a look at the door card seals as well.

I started taking out the carpet in the car (was hoping to get away with not removing the seat, no chance there) and saw how much foam was under there. Mine is absolutely soaked, so I am definitely going to have to remove the seats and let it dry properly.

I'm very curious to understand where the water is getting in from.

bertiejaffa
Joined: Fri 26 Jul, 2013 10:28
Posts: 1715

  M roadster S50
Location: Manchester

Re: Water in foot-well – the cure.

Post by bertiejaffa » Tue 02 Dec, 2014 19:14

If there is water under the seat it could also be coming in via where the soft top meets the rear of the car. Have a check in your boot as well. The reason is that under the carpet beneath your rear window the frame of the car has hikes so some water that leaks in here can go either into the cabin or into the boot. The best areas to check are in the side areas, ie under the plastic container on the right of the boot and also under the same spot on the left - this is where your tilt alarm would be.

Depending on the severity there is a product that will find small leaks - do a search on captain trolleys creeping crack cure
Here come the girls.....
Image
My //M Refurb
My First Zed Journal

Sailorbaz
Joined: Wed 26 Feb, 2014 10:07
Posts: 133

  M roadster S50

Re: Water in foot-well – the cure.

Post by Sailorbaz » Tue 02 Dec, 2014 22:31

Having just removed and rebuilt the entire interior of the Z3, I can confirm that removal of the front carpet is impossible without either cutting the carpet around the heater box of removing the heater box...which involves removing the entire dashboard. I'll be having a look under my carpets next time I'm home to check all my work is still dry after some of the mega rain we had in November before I come back offshore.

I don't have all my trim pieces on, so managed to get my hand under the carpet on the drivers' side and found it was dry, half a job done fingers crossed the passengers side is dry also.

ualla
Joined: Mon 10 Feb, 2014 16:37
Posts: 89

  Z3 roadster 2.0

Re: Water in foot-well – the cure.

Post by ualla » Fri 05 Dec, 2014 19:13

That does not sound like fun :cry:

ualla
Joined: Mon 10 Feb, 2014 16:37
Posts: 89

  Z3 roadster 2.0

Re: Water in foot-well – the cure.

Post by ualla » Sat 06 Dec, 2014 14:37

Took most of my interior out today (still struggling to completely remove the centre console for some reason) and I am pretty sure my problem is with the drain pipes where the roof meets the rear wing. The carpet behind the black plastic trim is damp there.

I can't seem to find the actual drain pipes though. Does anybody have a photo of where they are?

Brian4
Joined: Mon 19 Dec, 2011 19:02
Posts: 534

  Z3 roadster 3.0i
Location: Hinckley

Re: Water in foot-well – the cure.

Post by Brian4 » Sat 06 Dec, 2014 17:23

Hi Ualla
Not to answer your question on soft top drains but the scuttle panel drains.

Follow Del's instructions in the first post and some photos to go wiyh them

Wiper retaining bolt this is M16 spanner size
Image

Remove the bonnet seal.
Image

When removing the black scuttle cover be careful at this time if year as the plastic can be hard and brittle.

This is what the square tabs look like when removed.
Image

And this is the drain when viewed from under the wiper linkage.
Image

When you refit the plastic I squeezed the mastic back so that is was raised up and would seal against the windscreen when you refit it. Probably best to take the cover indoors and let it warm up.

Image

Hope this helps and you cure the leak. Short term answer could be a half cover till the warmer weather.
Brian
3.0I Topaz Blue


2000 E36/7 Z3 3.0i
2016 F31 335d
2015 F21 118i

ualla
Joined: Mon 10 Feb, 2014 16:37
Posts: 89

  Z3 roadster 2.0

Re: Water in foot-well – the cure.

Post by ualla » Sat 06 Dec, 2014 17:26

Thanks Brian, those images are really helpful. I will definitely check that drain tomorrow, weather permitting.

Luckily I do have a half cover so will be using that for now...

Really appreciate the images!

Uncle_Clanger
Joined: Wed 13 Apr, 2016 07:36
Posts: 20

  Z3 roadster 3.0i

Re: Water in foot-well – the cure.

Post by Uncle_Clanger » Sat 25 Jun, 2016 01:42

Found this thread today... Most helpful...cant afford another Yaw sensor! Thanks for the excellent photos Brian.
Brian4 wrote:Water in the footwell can come from 4 main places
1 as in the first post
2 from where the roof meets the top of windscreen.
3 from poor seal of the membrane behind the door cars as ours did.
4 the roof drains where the door meets the rear wing.

There is approx 2" of foam under the carpets so if the carpet has a puddle there is a lot of water under them and the water seems to run under the carpets rather than on top. I would check the drains first then spray a hose on the side window with the door open and see if any runs out between the door card and door and then check the roof seals.

Post Reply

Who is online

Users browsing this forum: No registered users and 10 guests