Technical Leaking windscreen

[fiat500]

I wonder if anyone has ever, ever really properly, fully, absolutely, in all honesty managed to a achieve a windscreen which doesn't gently weep heavy rainwater at the bottom corners. I have ever so carefully used the proper sealant all round and recently even put on another, layer overlapping slightly onto the glass at the corners...still leaks. The other windows have always been fine.
Any ideas PLEASE!!!

 

[Vitesse]

I thought the same as you, that I had put loads of sealant around the bottom corners but when it was parked outside last summer I did find some rain water had managed to get in. I think the sealant dries up after a while after it is first applied.

I plan to revisit again soon, just to stick some more in there and see if it solves it. I don't think it is only the bottom corners that needs a good seal. I think the rain water finds its way along the top seal and the sides. Then runs down to the corners and knowing that the bottom corners are the problem areas I think myself like everyone else probably concentrates too much on there and don't put enough in the other areas?

 

[Franko500]

Is it coming in around the glass or the aperture? My original front screen rubber was virtually bonded in with sealer hence the cracking. Also the glass was stuck in the rubber with sealer

 

[fiat500]

I think it's coming under the glass at the bottom corners but I agree, it may originate somewhere remote to this.

 

[stevehg]

On my defenders, I used to use a product called dum dum. It was excellent at sealing gaps or joints. You could also use on window rubbers where you felt they weren't sealing enough.

It turns out it's no longer available, fortunately I still have a tin, but here are a couple of equivalents of you want to give them a try...

http://www.woolies-trim.co.uk/c-121-putty.aspx

http://www.frost.co.uk/eastwood-flexible-strip-caulk-dum-dum-replacement.html

cheers, Steve

 

[fiat500]

I remember that "Dum-dum" stevehg. I had some in a yellow tin which I used on my old Austin. The modern windscreen stuff in a caulk tube is very similar although more messy.
I have been chasing these leaks with the stuff for months and I'm wondering now, as Franko500 prompted me to think, is it actually coming in around the ouside where it meets the bodywork? Ihad been thinking it came in under the glass which would seem easier to fix.
I won't need to wait long for a bit of rain to have look. I don't want Murf to be a dry weather only car.
I am pretty certain that Fiat themselves, unsuccessfully tried to deal with this issue with the ineffective drain pipes on the later models.

 

[fiat500]

After weeks and weeks of generally dry weather I have become used to leaving the car outside all of the time. Then today, when we took the grandkids to Nando's (yuck!) there was an almighty downpour and I was unable to get home to garage the car. So despite me repeatedly and more thoroughly over the last few weeks, attempting to stop water seepage using windscreen sealant and even using PU sealant in places, the steadly leak resulted in a fair-sized puddle under the floor rubber.
So this is the end of my patience and I really need to fix it properly. I'm questioning how effective the new seals are. Did anyone have to use sealant as well? Finally, is the rubber of good quality? I have found that most rubber items I hve bought last only a couple of months before cracking up.:bang:

 

[the hobbler]

Peter---does your windscreen have a (plastic) chrome insert in it? I have always been led to believe that one reason for the trim insert was to help 'pressure' the screen seal by spreading it, which helps prevent water ingress. I have an insert in both my front and rear screen seals and, to the best of my knowledge, have not suffered any leaking.
The answer might be to remove the screen, remove ALL gunge, re-seal the screen aperture with a thin layer of sealer, and then refit the screen with a seal that allows for the fitment of the insert, and fit the insert. There is a small tool for easy (well, relatively) insert fitment. 'Woolies' sell a kit of these tools--page 21 in their catalogue, part number '150' (although if your local garage fit screens, they will most likely have the tool and MAY be prepared to lend it to you)

 

[Vitesse]

All the rubbers on mine were new, as I said previously I had a few leaks, more like little drips when the car was left outside, it certainly was no where near enough to have puddles in the car. The rubbers have been fine but it doesn't spend any where near the amount of time outside as yours does. I also bought some windscreen rubber conditioner to put on the quarter light rubbers as they were original and showing their age. I was a bit sceptical but it does actually work, they look like new now and I treated the rest of the rubbers to it as well, so maybe thats why the are holding up better? Its called GUMMI PFLEGE and costs about £5.

When I sealed them it took ages to do and I had to pump loads of the sealant in using a caulking gun, there are some really big gaps hidden away under the rubbers. I think I used 3M on recommendation from someone on the Old Classic Car Forum.

 

[Franko500]

Water, rain!
Last Saturday I took my car to local car show all cleaned and polished. An hour in, lightening and thunderstorm. I sat in the car waiting for the leaks to start.
Nothing!
I have new seals with chrome insert and used sealer between rubber/body & rubber & glass.
Car now safely back in garage clean and dry. Although he has been out quite s lot recently since changing the carb.

 

[fiat500]

Thanks all; that helped me decide what to do.
To recap, it is usually just a weeping leak and definitely between the seal and the glass. The rain today was incredible over a short time and it follows me having done some sealng recently which seems just to have just chased the leaks about.
I can see the logic of the chrome insert putting pressure on the seal, but I don't want to make yet another visual change.
I remember when I fitted the glass units into our sophisticated Danish double-glazed frames there was some PU sealant supplied specifically to be used in the bottom corners, so may be it's a law of physics that I'm fighting.
New seal to be obtained and fitted with PU sealant all round.

 

[fiat500]

An incidental to this is that I got to grips with the (thankfully) surface rust the regular drips had caued to the floor under the sound-proofing. All treated with phosphoric acid now and drying out thoroughly prior to painting with epoxy.

IMG_20170604_170346 by Peter Thompson, on Flickr

 

[John Bewick]

I have been told by C O H Baines of Tunbridge Wells who still make a lot of rubber mouldings for classic cars etc, that due to EU laws some of the chemicals that used to be used in rubber production are no longer allowed.
The result of this is that the rubber can not be made as soft and complient as it used to be, hence it will not conform to the shapes of screen apertures as well and is also more affected by UV light making it brittle causing cracking.
This is probably the reason most modern cars have very little rubber used on the outside, and very often when it is it is often covered by a trim, and nearly all screens are now bonded.
The only thing we can do is to seal all round the glass and frame with a flexible and non hardening sealer.

 

[fiat500]

I think I have finally cured this problem which may have been with my car since day one judging by the amount of black stuff around the glass when I bought it.
I had despaired of ever curing it and decided to give it one last chance before buying a new seal; it currently bears the original 49 year old seals in all windows...me being a stickler for originality and all that. So I tracked down this stuff:

https://www.permatex.com/products/a...ex-flowable-silicone-windshield-glass-sealer/

....flowable silicone. It's not cheap and comes in quite a small tube. It comes with a very thin applicator nozzle which is good for getting under the lip of the seal. It really does flow and eventually dried with a bit of surplus squeezed out of the seal although I deliberately avoided putting any pressure on the rubber.
Whilst the first application in the logical places where I saw water getting in did reduce the amount of water, it also had the effect of making it clear that some of the water was gravitating from about half way up the sides of the screen, which I hadn't anticipated. So after a few days of dry weather I put a bit more on.
It's been tested under a fair few April showers now, both parked up and moving and it looks like it's fixed.
This is the second Permatex product I have recommended; the first being their grey instant gasket.

 

[Bigvtwin996]

I think I have finally cured this problem.......

what's wrong with Gaffa tape!! works a treat...
I even managed to seal a leaking sunroof and a split rear window... (well on the protoypi it's plastic)
all with the same roll...

 

[fiat500]

Gaffa tape would be fine but it's not that custom look I'm after.

 

[F123C]

This topic was covered back in Jan. 2018.
My contribution was www.fiatforum.com/500-classic/456384-front-windscreen-install-sealer-needed.html#post4313208
(Idk how to copy a previous post to this thread , no good with computers!)

I see 'fiat500' (Peter) managed to find a supplier/brand of the 'creeping' clear sealant I mentioned.

Another product Permatex do is a thread locker/sealant, often stocked where Loctite products aren't!

AL.

 

[fiat500]

Last week we had a couple of days of downpour and the leaking came back. I had a brand new seal in waiting so on a really hot day I pushed out the screen and replaced it. The old seal split along the original joint and although it otherwise still looked OK the new one was tighter and needed a fair amount of force in order to get the glass into the grooves. It was easy to clean off the black, non-setting sealer from the glass, but the traces of silicone have been a nightmare. It took less time to replace the seal than I've spent in total on bodging repairs!
Now I need some rain to test it.... shouldn't have to wait long.

 

[Vitesse]

What’s this thing called rain you are referring to?

 

[fiat500]

What’s this thing called rain you are referring to?

no sign of it at the moment I must say.......