Sliding-window leak

[boxelder]

I hear you, but the drain slots on my windows are definitely clear and water flows freely through them to the vehicle exterior.

Yeah, wasn't doubting it. I suspect the slot is curved and some folks (me included initially) think it's blocked. As shit gets washed in though, it will block, so keep checking with that light.

 

[.50]

@.50 - brilliant video, thank you and it's helped clarify the most likely point of ingress which I couldn't figure out! Similarly to you, I've done a bit of investigating but on the exit point rather than entry and uncovered what I think might be a possible issue with one of the round drain holes on my leaking window (sliding-door side only, 2018 T6 Kombi). It might apply to the second one as well but haven't yet investigated. I came up with the following:-

- I removed the lower plastic moulding from the window assembly
View attachment 88128

- checked the two drain slots which were clear and evacuated the water well
- the pan or tray you refer to underneath the round hole can be eased away from the upper moulding. It's fixed in place by some kind of mastic.
View attachment 88129

- this shows that the mastic should sit in its own channel to form a seal around the tray that water drips into through the round hole immediately above. The water then disappears out through the same exit as the slot.

View attachment 88131
View attachment 88130

- however, the picture shows how poorly the mastic is distributed around the tray and in some places it's virtually non-existant, providing a clear path for water to escape out into the lower trim and then onto the window sill below.
- I cleaned out the tray and neatened things up as best I could to provide a more even seal. The tray returns to its natural position and is held firmly in place by the mastic.
- pouring water into the hole from the channel above showed that the leakage was measurably reduced but some water was still getting through. I'm fairly certain that the manufacturing process is poor (done by hand or robot?), resulting in random effectiveness of the tray being sealed - maybe that's why some vans have the problem and others don't?

Question for the forum: This seal needs to be better. Any ideas as to what this mastic is and where to get hold of some? Failing that, would the sealant that .50 used be suitable? Thanks all - this forum is a huge help to me as I'm very much a newbie to this sort of thing!

Your investigations and post are great, and go further into the lower workings of the bottom window guide.

I am now on a quest to get hold of a genuine VW window that has been removed so I can get detach the bottom guide and really see how its supposed to function.

I suspect, as you suggest, that its probably not a bad design, just one that is intricate and needs care taking when being manufactured.

 

[Petro]

This might help. T5 Sliding Window leak, Finally fixed

 

[nrgnet]

Hi rph - that's a great thread, thank you for sharing.

 

[Sharkybooster]

I know there's other threads about unblocking drain holes but looks like my leak is caused by a broken rubber seal which has let water in and the window has rusted, anyone else seen this?

 

[osman]

Hi, I had the same issue. One was fine but the other leaked. I attempted to remove with cheese wire but chickened out. I ended up going to a specialist vehicle glass company who removed, cleaned and re-sealed for £40. In my opinion it wasn't worth the risk of damaging the window/paint for what it cost for them to sort it.

I’m having a similar issue .. cannot find where water is coming in but it’s pouring in somehow down the side of my sliding door window into the door !! The window was fitted by previous owner .. can you tell me where you got yours fixed for £40 ?

 

[Garny999]

I’m having a similar issue .. cannot find where water is coming in but it’s pouring in somehow down the side of my sliding door window into the door !! The window was fitted by previous owner .. can you tell me where you got yours fixed for £40 ?

It was these guys, brilliant service...

Lancashire Windscreens | Windscreen Replacement | Windscreen Repairs | Side Glass Replacement | Blackburn

Lancashire Windscreens supplies and installs windscreens, windows, sunroofs, side glasses and wipers. We also provide repairs and replacements for chipped and damaged windscreens

www.lancashire-windscreens.co.uk

 

[zlea73]

hi I tried most fixes I could find online I taken out the window drilled a slightly larger drain hole, silicone in the gap between metal panel and plastic frame I also used some silicone grease on the seal. unfortunately I found out the seal around the sliding window is broken.
looks like previous owner of some kind of glue. Do they sell that seal? I googled a lot but couldn't find a code for a kombu window.
them I bought a replacement kit (sorry terrible picture) but I don't understand where the little plastic cilinders go.
looks the same size of the metal pin who runs in the rail. but its made of plastic????!!
any help?

 

[MikeD29]

My 18 reg T6 campervan has leaking sliding window (now taped up) It also has white marks around the black backing to the windows (see image). These are only visible in direct sunlight. It looks as though the black backing is breaking down. Has anyone experienced this problem or has any idea about the cause. I've been back to VW van centre a couple of times but so far no luck with a resolution.

 

[oldiebut goodie]

https://www.t6forum.com/threads/leaking-kombi-windows-how-to-guide-to-resolve.3570/post-345844

Success at present with no dismantling - silicone grease on the seal and also an old favourite, Captain Tolley's Creeping Crack Cure applied to the bonding along the top edge at the body side and fixed glass side using a syringe. I have gone from Niagara Falls amount to not a trace of damp. I blasted everywhere dry with compressed air before starting. Had a fair bit of rain since so am hopeful it has done the trick for a while. I noticed that with the application of the cure to the top outside that some made its way to the base of the catch panel ( it is milky white until cured so is noticeable) so it was obvious that there was an easy route from outside at the top between the bonding and one of the surfaces to the interior.

Still dry!

 

[Leighjcj]

Did the same as this on mine. Completely dry since

Update:
I removed both opening windows yesterday from my twin sliders to inspect why or from where I was getting leaks.

My issue was exactly the same as the video link posted previously where the gutters are working, but water was leaking between the glass and the plastic gutter mouldings and then seeping between the plastic parts and dripping into the van.
To start with, the lower gutter / drain deflectors seemed well position and showed no signs of being lose or needing re-sealing. They did however show signs or where water has been saturating the surrounding areas easily spotted by the discoloured marks.

So I dried everything and put a tiny bead of black stixall silicone into the channel to seal the tiny gap between the glass and the plastic channel.
Came out this morning and retested and happy to say, So Far So Good. I’m not getting any dripping underneath and the water is exiting via the drainage slots well.
I’ll refit the windows later and do a hose test..... watch this space (fingers crossed)
View attachment 104713View attachment 104714

 

[askwithvdub]

I had a T5 that suffered from the leaky windows (Both sides) I had two new replacements on warranty.
Now I have a new 6 and NO LEAKS so far, seems VW have a solution they have tightend up the clearances so much so that one side is difficult to open and close the other side is impossible to operate....
Went in today by appointment and VW sent a parts kit fix that includes a new sliding window.
Oh guess what they forgot to send the window !!!
To achieve a solution to a problem you must first recognise that you have a problem.
Wakey wakey VW you are spoiling the ship for a hapth of tar

Hi
New here today. I have had my T6 combi now for a week. After last nights bad rains guess what?. Window has leaked. Puddle on the foot plate where you step in!!. Back to the dealer?
Whats your thoughts people?

 

[Andysmee]

*sigh* ...sending hugs your way

 

[MikeB]

I'm planning on giving up on these useless windows in ours as we never use them anyway. I appreciate that I could just silicon them but much prefer a more nuanced solution rather than a bodge, so the current thinking is to have them replaced with one piece glass. Is this just a matter of talking to our local w/screen repair folks or is it more complicated? They'll need to match the tint as well of course.

 

[Eddie Sutherland]

Order the glass from camperglass.co.uk and have a windscreen company fit them or if you know a fitter get them to do cash

 

[SaraG]

So I figured out my window leak wasn't my window at all... it was the "carpet" that was fitted around the door that was breaking the seal of the door & van. The water was being drawn in as the door seal wasn't able to do its job, and the water followed the line of the window down which made it look like the window was leaking on to the step inside. Solution was to carefully cut back the "carpet" away from the door seal - obvious when you point it out! I've had no leaks at all since I did this. We've had some big downpours recently too, but I'll will keep checking. Might be worth checking your van set up, I was convinced it was the window.

 

[boxelder]

Easy to tell if it's the window, by popping off the plastic trim forming the base of the slider. No water there, no leak.

 

[Ali-G]

Rechecked mine the other day after a particularly heavy downpour, still no leaks after just cleaning and Gummi Pflegeing the seals.

 

[Eclipse Custom Vans]

So I figured out my window leak wasn't my window at all... it was the "carpet" that was fitted around the door that was breaking the seal of the door & van. The water was being drawn in as the door seal wasn't able to do its job, and the water followed the line of the window down which made it look like the window was leaking on to the step inside. Solution was to carefully cut back the "carpet" away from the door seal - obvious when you point it out! I've had no leaks at all since I did this. We've had some big downpours recently too, but I'll will keep checking. Might be worth checking your van set up, I was convinced it was the window.

So many people line like this and I can’t believe they do, but as you say it obvious that you shouldn’t interfere with the sealing....

 

[MikeB]

Rechecked mine the other day after a particularly heavy downpour, still no leaks after just cleaning and Gummi Pflegeing the seals.

Interesting - stick or spray?