Z3 Boot Condensation

Gatsoburner

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British Zeds
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3.0i
Anyone tackled the issue of damp in boot lid after cold nights.?.

Im considering adding some closed cell insulation, reading up it appears it'll be a barrier to the cold air accumulating overnight.

I'm going to give it a go overnight then take it off and see whats what, opinions??....
 

Mint

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East Anglian Crew
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Stafford
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You probably need to make sure there is no dampness already in the boot as that's where the water to form the condensation is coming from.
The usual suspects for leaks are the aerial grommet and the 3rd brake light seal. Very rarely the light units seal.
 

Pond

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Spaldingski, Lincs
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3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
Anyone tackled the issue of damp in boot lid after cold nights.?.

Im considering adding some closed cell insulation, reading up it appears it'll be a barrier to the cold air accumulating overnight.

I'm going to give it a go overnight then take it off and see whats what, opinions??....
I think the problem is related to your other thread regarding the roof and water in the boot.

Unless there is water present in the boot you can't get condensation on the inside of the bootlid. Insulation ain't gonna fix the problem, just divert it to elsewhere.

As I'm sure you are aware, electrics and moisture do not go well together. And there are a lot of electrics in the boot of a Z3; not least the battery!
 

Gatsoburner

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All points in the boot are dry, no dampness in any corners or floor, I check it every time I open the boot. Back bulkhead, sides removing carpets, boot removing floor. I sealed the 3rd brake light and am confident it's dry, no runs of water with lud open on the interior skin so to speak.
I was thinking the metal boot lid is so thin and cold overnight it creates coldness thus condensation, like warm meeting cold on house windows, moisture to droplets to condensation occurring.

Only reason I'm thinking this is, ive been putting a towel across the boot lid under the outdoor cover, it's dry inside the boot lid every time.
 
Last edited:

Pond

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British Zeds
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Spaldingski, Lincs
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3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
All points in the boot are dry, no dampness in any corners or floor, I check it every time I open the boot. Back bulkhead, sides removing carpets, boot removing floor. I sealed the 3rd brake light and am confident it's dry, no runs of water with lud open on the interior skin so to speak.
I was thinking the metal boot lid is so thin and cold overnight it creates coldness thus condensation, like warm meeting cold on house windows, moisture to droplets to condensation occurring.
Condensation can only occur when there is enough moisture in the air. To get condensation on the bootlid, the air within the boot needs to be excessively humid. You have got moisture in there somewhere. Doesn't need to be much..but there is too much, hence it condensing out onto the colder bootlid.
 

Gatsoburner

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Hmm..I'm wondering if the rear light clusters are holding water, outer seals look poor ish, no water visible but I guess they could be damp.

I shall continue my quest, Feel like Aquman faffin about with water issues on the car.

Anyway, newbie winter cover on tonight, see what comes tomorrow 😊
 

Pond

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British Zeds
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Location
Spaldingski, Lincs
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3 litre Z3 pretending to be Italian exotica. Two previous E89 Z4s.
I shall continue my quest, Feel like Aquman faffin about with water issues on the car.
Welcome to the world of convertible ownership! I have had much newer convertibles than the Z3 and have had the same issues. Basically, the UK ain't the best place to own a convertible.
I had a £35k F33 BMW convertible with 2 gallons of water sloshing about inside the rear wings. You could hear it. I have had an E89 where the battery was almost floating.

My Z3 had gallons (and I mean gallons) of water inside it when I got it. Fried several very expensive pieces of electronics aswell.
 

Gatsoburner

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We had an 07 A4 Convertible which was good until thr cam chain chewed itself up. 3k. Later it was back on the road.
Boot roof motor was the only other issue due to the electric motor brushes being dirty often causing a poor connection.
I'm sure once spring comes I'll get on with driving the car and enjoying ourselves.

MOT Monday which I'm pretty hopeful should be a straight pass. Done all the checks I can myself so fingers crossed. Garage quoted £250 for an undeseal which I'm tempted by, anyone else sealed theirs ?..
 

colb

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Old post here about fitting a liner to the boot lid, I put one in mine much the same as this one.
 

ChrisD

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Vale of Evesham
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M44
I’ve used Lanoguard. Self applied so you can have a good check of the condition of everything. Really easy to apply and, other than a sheepy smell, mess free.
Good luck with the MOT.
 

Gatsoburner

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Old post here about fitting a liner to the boot lid, I put one in mine much the same as this one.
Ah great..cheers👌
 

Gatsoburner

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I’ve used Lanoguard. Self applied so you can have a good check of the condition of everything. Really easy to apply and, other than a sheepy smell, mess free.
Good luck with the MOT.
I'll have a look at that, keen to do something. Cheers 🍻
 

Nodzed

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Check the left hand well, pull the carpet Back from by the rear light, there's a deep well there that houses an alarm module put your hand deep into it to check for water, it's a regular spot for water from a leaking aerial grommet if it's gotten in there's no way for it to get out.
 

Gatsoburner

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North West of UK
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3.0i
Check the left hand well, pull the carpet Back from by the rear light, there's a deep well there that houses an alarm module put your hand deep into it to check for water, it's a regular spot for water from a leaking aerial grommet if it's gotten in there's no way for it to get out.
Yes, had that one and solved it. New alarm module was my first job, never seen so much water sat in a car panel. Ruined the module but secured another and refitted. Decided to fit upside down just in case but its been dry since mid December
20251216_143800.jpg
 
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