Next Question - Leaky windows

Stemar

Stemar

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Jazzcat's windows are mostly glass in aluminium frames with rubber seals shaped a bit like a windscreen wiper blade on the outside. The seals have shrunk and they leak. Having experienced this kind of seal before and tried to replace it with a notable lack of success, I't like to use a sealant to replace the rubber.

Plan A is to remove the seals and give glass and frame a good clean, allow to dry and fill the space with a suitable goop. The goop needs to stick like the proverbial to a blanket, be weather and UV proof and preferably be black. Ideally, it also needs to be removable if and when the time comes to do the job properly.

What goop would you suggest? Any other thoughts?
 
I just used clear window frame sealant from Screwfix applied on glass /frame and frame/coach roof joins; I’m sceptical about the cost/benefit of sending them to be done professionally - still have to seal them back into window openings yourself
 
I don't think - possibly a little misplaced optimism here - that the joint between the frame and the coach roof is the leaking. If it is, it'll be a matter of removing them and redoing with butyl tape. My current problem is between glass and frame. I've never had much luck with new rubber seals, which is why I'm thinking of a sealant.
 
I'm doing it right now.

I'm nervous of setting polyurethane as its a one way street.

You might be able to find the right rubber section, there's a useful guide on the sealsdirect website, but I found in practice that its impossible to pull the whole thing together.

I've cut some 1" lengths of the correct section to fill the gap between glass and frame. Trial assembled. Then a thick bead of non setting arbomast br in the bottomnof the channel in the frame, assemble and clean up. Then I masked off glass and frame and applied a bead of black silicone. Turn over. Repeat masking and silicone.

I think it will work, I'm quite sure I could disassemble if needed.

I'll take some pics.
 
The glass fits into a U shaped frame with a U shaped rubber seal. The channel is rivetted together with little jointing strips. I think replacing the seals is not possible without disassembling the whole thing. When I had a front window broken by another boat in a berthing mishap I thought it would be an easy job to replace the glass myself. I did it but it was very difficult and I set the glass into the channel filled with sealant. It is tempting to wish to do the job properly but be aware it is a tricky and time consuming job. I think the suggestions about Capt Tolleys is worth a try.
 
Stemar said:
Jazzcat's windows are mostly glass in aluminium frames with rubber seals shaped a bit like a windscreen wiper blade on the outside. The seals have shrunk and they leak. Having experienced this kind of seal before and tried to replace it with a notable lack of success, I't like to use a sealant to replace the rubber.

Plan A is to remove the seals and give glass and frame a good clean, allow to dry and fill the space with a suitable goop. The goop needs to stick like the proverbial to a blanket, be weather and UV proof and preferably be black. Ideally, it also needs to be removable if and when the time comes to do the job properly.

What goop would you suggest? Any other thoughts?
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I rebuilt the windows on my 9m many years ago. A bit fiddly and time consuming but well worth it, apart from the hopper windows. Still can't get them 100% water tight. I will try to find my article I wrote for the BCCA (Bobcat and Catalac Cruising Association) at the time. If you send me pm with your email address I will send to you - as long as I can find the article in my filing system !
 
We replaced some of ours, last year, which were acrylic and had cracked. The acrylic was seated on a gelcoat fibre glass recess and I believe the original adhesive was a 3M product used to hold windows in high rise buildings, the Petronas Towers in KL was one application.

We removed all the relevant acrylic and cleaned up the old adhesive. This needs patience, do it one window at a time. We reseated the new windows, again acrylic, with an adhesive that I assume is similar to the 3M but is part of the Sika range - specifically for sealing windows. Its not an easy job replacing the windows, needs 2 people, as our windows are 1m in some dimensions and you need skill to drop the new window into the right place. Mark the windows on the inside and out with masking tape so you know that it will be dropped onto the adhesive correctly. You need lots of masking tape. Our windows are dark, tinted, and look black from the outside so the Sika is also black and the Sika extends about 10mm beyond the windows and is part of the decor, both inside and out. Our acrylic overlaps the gelcoat by 100mm - so we needed a lot of Sika.

It takes a long time for the sealant to set off and we used 20l water bottles as weights on the outside and the sucker things used to carry plate glass and tensioned on the inside with rope. I depends on your interior we were able to rig up 'strong points' to provide the anchors for the tension ropes but if you had 2 sucker device things you could have one on one side the other on the replacement windows and simple a rope that you can tension in between.

I'd remove the frames, if that is actually possible without damage, and re-seat - its a bit of a waste of time and effort to re-seat the windows if the frame adhesive is 40 years old.

It takes a long time to remove one window, clean up and re-apply the window - work on one window at a time or you may find you remove a window but don't have time to make the hole weatherproof - and the forecast for the next day might be wrong.

We found with the first window that we could see the gel coat (white) inside and had to take one window out with 'wet' Sika (frabtious day :( ). WE then had to make sure that the Sika was spread evenly covering all of the gelcoat. Windscreens in cars are a abraded and then painted black round the edge, I assume for a similar reason. I also assume its special paint as ideally you want a strong bond and normal paint would not offer that bond.

Some of our windows were slightly bowed and we screwed hard wood battens to develop the bend, screwed into the cabin roof. The screw holes were then hidden in the 10mm Sika edge and filled when the Sika had set off (takes days to develop full strength - so do one window on side one day and another window on the other side the next day, or 2 windows one one side etc (depends on window size).

Before we embarked on this adventure I spoke at length with a Sika technician, here in Oz, and he went through the procedure necessary very thoroughly.

After 12/18 months the new windows have been fine.

I have some pictures if it would be useful of how we used the water bottles as weights - they are on another computer (and I'm lazy if they will not be useful).

Think through carefully how you are going to do this - talk it through with your wife, its not complex but Sika is so messy - one mistake and you will spend an afternoon cleaning up! You need to clean of any Sika that squeezes out, there and then, as if you have battens or water bottles you lose access to the window. Packing tape will hold the windows in place when you clean up - you can then add the weights etc - if needed - but you will squeeze out more Sika when you weight up and tension (masking tape is your friend).

Once you have done one - you will work out the best way :)

Good luck

But once you have finished it is immensely satisfying.

Take care, stay safe

Jonathan
 
Stemar said:
Jazzcat's windows are mostly glass in aluminium frames with rubber seals shaped a bit like a windscreen wiper blade on the outside. The seals have shrunk and they leak. Having experienced this kind of seal before and tried to replace it with a notable lack of success, I't like to use a sealant to replace the rubber.

Plan A is to remove the seals and give glass and frame a good clean, allow to dry and fill the space with a suitable goop. The goop needs to stick like the proverbial to a blanket, be weather and UV proof and preferably be black. Ideally, it also needs to be removable if and when the time comes to do the job properly.

What goop would you suggest? Any other thoughts?
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I did my aluminium framed windows with pu40 between glass and frame and caravan butyl tape between frame and hull. Complete success!
 
I can see how much of a faff redoing the windows properly is going to be so, since I don't think there's significant leakage twixt frame and cabin, I don't want to disturb that joint until I absolutely must. My problem is that the sealing strips mentioned by CO8 have shrunk - inch gaps on some windows and soggy cushions underneath, so it's them that I hope to replace with a glazing seal, Captain Tolley may work for tiny seepage, but not the big gaps with free-flow dripping that I've got.

The opening (hopper) windows are another matter - they will require some serious thought, but the worst leaks aren't from them.

Thanks all!
 
I did mine two years ago, same type of window, heck of a job, getting the frames apart was very difficult, and removing the old gasket was almost impossible, one window took the best part of a day to clean everything up. I used a non setting rubber sealant from screw fix which seems to do the trick, it's goes off like a soft rubber.
The other window has developed a leak now, but I'm putting off the job.
Edit, just remembered that there were little rubber grommet type things that held the glass in the centre of the frame so as the sealant can be equally distributed.
 
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Stemar said:
I can see how much of a faff redoing the windows properly is going to be so, since I don't think there's significant leakage twixt frame and cabin, I don't want to disturb that joint until I absolutely must. My problem is that the sealing strips mentioned by CO8 have shrunk - inch gaps on some windows and soggy cushions underneath, so it's them that I hope to replace with a glazing seal, Captain Tolley may work for tiny seepage, but not the big gaps with free-flow dripping that I've got.

The opening (hopper) windows are another matter - they will require some serious thought, but the worst leaks aren't from them.

Thanks all!
Click to expand...

What about the clear Car Windscreen Clear sealant you can buy in Halfords etc. Its thicker than Tolleys ... designed to actually fill gaps .... being from the time when car windscreens were in rubber U channels and not bonded - that stuff was always in my tool-box !

It does not set as permanent so later you can do the job properly.
 
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Sikaflex 296 will seal and glue the glass to the aluminium frames. Hadlow Marine as noted above by UK-WOOZY, did mine. They are coming up for 7 years in use and bone dry, far better than any seals.

I supplied the frames split to Hadlow Marine who did the job. What I suspect they did was stick the glass into one half of the frame first either using a jig or carefully supports. Perhaps by supporting the glass and then offering the frame up with some blobs of Sikaflex to set and hold in place, or maybe firm rubber blocks to clamp the glass in place, but buried deep in the frame. Then repeated for the other half. I don't know.

The frame though is full of sealant from the bottom to the outside edge, where it is chamfered at 45 degrees inside and out. This allows the water to run off and not pool, even when healed over. The sealant is fully penetrating as there are corrosion holes in the lower section of my frames where the sealant has been smoothed flush.

There is no reason why it cant be done DIY. Good luck.

Edit - wrong Sikalfex product quoted, now changed.
 
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