bad leak behind passenger seat

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Joined: Sun 10 Jul, 2016 13:48
Posts: 2

  Z3 roadster 3.0i

bad leak behind passenger seat

Post by craig1 » Wed 20 Jul, 2016 20:59

i have had to spend several hundred quid replacing electrical connections under the passenger seat caused by damp which appears to have been coming in for some time, but resulted in the carpet under and behind the passenger seat becoming drenched back in the spring (which i thought was down to the wife not closing the door properly - apparently not!)
local garage took at look to find any leaks and suggested i needed to replace the roof seals which may have shrunk 'and see if that sorts it out' at a cost of £600 for the seals and 5 hrs labour! I spoke to the helpful guy in croyden at soft tops as recommended by many posts on this site, who suggested there are a variety of places water could come in so im concerned that im being stitched up by the garage for £1000 plus when it could be a simple thing. Ive been through the posts and doesnt seem anything similar, and everything seems to fit ok. If i didnt live 5 hrs from croyden i would probably ask him to look at it...

love the car but its getting expensive!

any suggestions?

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  Z3 roadster 1.8 TU
Location: Newport South Wales UK

Re: bad leak behind passenger seat

Post by colb » Wed 20 Jul, 2016 22:41

First check the drain tubes at each side of the hood pivots are not blocked, previous posts on these. Could be the joint under the back window if the seal along the back edge of the hood has started leaking. Probably best way of checking would be to remove the seats and get someone to spray a hosepipe over the roof whilst you are inside the car looking for evidence of leaks. Previous threads on the rear hood seal. Door seals could also be a cause. You really should take the carpets out to dry them out so seats do really need removing to do this. Whilst you have the carpet out it may be easier to spot any leaking areas.
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  M roadster S50
Location: Manchester

Re: bad leak behind passenger seat

Post by bertiejaffa » Wed 20 Jul, 2016 22:46

That is very expensive - I wouldnt go anywhere near them.

Peel back the carpet under the back window. If the water is coming in from there you can usually see the run marks on the metal... that said if it is coming in from there you usually get puddles and wet in the boot too.

On mine I had a leak where the seal met the 1/4 light on the door frame (if you look the seal goes in just slightly) I fixed it byputting some sealant under the seal to force it up to meet the door better. A lot of people swear by gummy phledge to treat the seals as well.

Remember that water coming in from the front can still end up in the back of the cab as it will travel.

Best to put a hose on the car and sit in it to find where the issue is coming from
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  Z3 roadster 1.9

Re: bad leak behind passenger seat

Post by BonBon » Thu 21 Jul, 2016 08:33

If as Bertie says you see the dribbling of water when you pick up the carpet of the storage area behind the passengers - you can reinforce the seal adjacent to the boot from the outside when the roof is down.I used black Super7 (my favorite silicone sealant) after I had a new roof installed and it is holding for over 4 years. ... -oz-290ml/

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  Z3 roadster 2.2i
Location: Basingstoke

Re: bad leak behind passenger seat

Post by wonderloaf » Thu 21 Jul, 2016 08:44

It's worth looking at the waterproof membrane behind the door cards as well, I had water getting under the passenger seat due to a split in this part. The water comes in at the bottom of the window and leaks out at the bottom of the door between the door card and door frame, when it happens you would hardly know it's there. Easy to check, with the door open pour water along the seal at the bottom of the window and check for leaks at the bottom of the door.
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  Z3 roadster 3.0i

Re: bad leak behind passenger seat

Post by craig1 » Sat 23 Jul, 2016 08:22

Great thanks for all the advice....thought it would be better to check the possible or common causes before shelling out for work that's probably not needed.....much appreciated! :) :)

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  Z3 roadster 3.0i
Location: Hinckley

Re: bad leak behind passenger seat

Post by Brian4 » Tue 26 Jul, 2016 18:49

Where are you based as there is a help guy in Coventry who repairs softops?
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  Z3 roadster 2.2i
Location: Redditch

Re: bad leak behind passenger seat

Post by Vic-Z3 » Wed 27 Jul, 2016 20:42 ... 52#p338852

Maybe of some use ........................ :thumb:
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