Got a bit of a leak through the side windscreens on the boat. Don't really want to take the whole thing off and reseal it as that would be a huge job.
Has anyone found a suitable sealant/mastic I can use to improve the existing seal?
Toughened glass in aluminium frame. Not sure what the existing sealant is but its black, dried out and a little bit crumbly.
Per Ardua Ad Nauseam
You could try Captain Tolleys leak cure. However, in reality it is likely to be only temporary and at some point you will have to bite the bullet and take the frames out and reseal them.
I am afraid I don't have good news either. Most of the windows on my Nauticat leaked when I bought her and I threw much good money after bad trying various resealing techniques, all ultimately unsuccessful, until I bit the bullet and bought complete new windows. However, I learnt plenty along the way, which might be useful for you.
Try to work out whether the water is coming in between the glass and the seal in the frame, or between the frame and the boat: get the hose on it whilst someone looks inside.
If the former, you can try captain tolleys but it only really works if the gap is small, the rubber seal not too deteriorated and there is limited movement. The other alternative is to remove the glass from the frame and reinstall with the new rubber seal if you can match the profile (there are various online companies who sell window rubber profiles) or bed down in a purpose made sealant such as Terodicht vehicle window sealant from Terostat Henkel (what is used to glue the windows into coaches etc). The issue you will have is getting the glass out and back into the frame. You may need some help from someone with a suitable press if the window is a one piece construction, rather than a split construction that allows you to dismantle the frame. I found that even if they have screws or rivets to allow disassembly, they were so corroded they often just fell apart anyway.
If leaking around the frame between the boat, get the window frame out of he boat and clean up the boat and frame with acetone and 1200 grade wet and dry, replace the rubbers on the frame and reinstall. If the frame sits in sealant rather than rubbers, use Sikaflex to reinstall, but this will make it hard to get the windows out again if you need to, but I found silicon just doesn't keep a seal. Put the window back in on the Sikaflex sealant, and do the screws up about 50%, leave for 48 hours and the tighten all the way to create a really good, flexible seal.
Finally, I met a fellow Nauticat owner who had cured a leak between glass and frame by taking a very sharp scalpel blade and cutting at 90 degrees to the glass around the inside of the frame, basically cutting away the rubber seal that is visible between the glass and frame, cleaning up with acetone and then putting in a filleted bead of black UV proof Sikaflex (291U I think it is). I have not explained it very well i am afraid, but he had some success with this and reckoned it lasted 2 to 3 seasons before he re-did it.
Last edited by Puggy; 20-05-12 at 15:26.
Reason: Had a last minute thought
Agree with finding out where the leak is. If it is the frame / boat joint I now use arbomast br non setting sealant that does allow the item to be removed even years later.
Originally Posted by Puggy
Its definitely the frame/glass seal
Originally Posted by Boathook
Per Ardua Ad Nauseam
Captain Tollies, is the best answer, and it will do one of two things, if the gap is small, it may seal it, if a bit larger, you will see where the white Captain tullies is coming through. So concentrating on that bit, Tulleis will mend it, at least for a while.
Originally Posted by RIN
I presume we are talking mastic sealed windows here, not a rubber type extrusion.??
Eventually Tullies, will look a mess, or just cant cope. The problem is, fiberglass is flexible and glass aint. So best mend I got was from a bloke, that gouged out all the muck, then painted the glass, with some special stuff, just round the edge. So then the Silkoflex or whatever, stuck to the window and the flexy bits did there job, by flexing, but not becoming unattached to the glass.
So all you need to know now, is what was the stuff.
I used Flexitape,its a non setting butyl compound in tape form,easy to apply .you fix one side to the boat,remove the paper tape and install the wndow.apply the ally frame and tighten,this oozies out the butyl.remove excess with 1/2 a wooden clothes peg,job done.Did one of my windows about 5 yrs ago and still OK.I got it from a local glaziers,he said it had a 20yr g/tee.