We have a leak on the front corner of our 1996 Dawnstar. Having done a bit of reading on here I decided to remove the awning rail clean up and reseal it before tackling the damage on the inside.
Problem is I can't get the awning rail off because it looks as though it has been bonded on with Sikaflex or similar. This has thoughly bonded the awning rail to the Aluminium sheet on the van side, but there was nothing bonding/sealing to the plastic front panel of the van - hence the leak. We've owned the van since 2002, so Sikaflex or what ever, must have been done before this.
So do I:
1. Clean up the void best I can, pump a load of sikaflex into the gap and pull the rail back in with some long screws.
2. Continue pulling at the rail until it comes off - this is proving very difficult and will probably just wind up pulling the aluminium skin of the side panel or at least significantly weaken the bonding of the side panel.
I'd like to keep the van for another 5 years or so, as it has been a very good van todate and this is the first leak/damp problem we have had with it.
Thanks birdman, I've Tried cheese wire in the form of fuse wire. I've got pretty strong hands but I can't pull either a blade or wire though the glue. Trying to sort out how they remove the Sikaflex from cars when they fit a new windscreen. I'd like to remove the rail, but it is stuck fast.
yup you have a real problem here, I came across a similar problem a few years ago, It basically turned out to be a 2 man job. I had to cut through it with a Stanley knife, with the other person gently pulling it away from the van. Make sure the other person doesn't pull it too hard or the rail will bend. i then had to use a sharp chisel to clean the remainder of the side of the van and awning rail before resealing. It took from 8am till 7pm to do one awning rail.
Thanks birdman 101, I've tried a cheese wire and it doesn't work, because the rail just over hangs the end of the Aluminium sheet i.e. the aluminium sheet is completely under the rail so there is no way to get a cheese wire or knife into the one side. To remove the rail I would need to completely distort the aluminium panels from ground level upto the roof level.
Yes thanks Oxter, I definitely have all the screws removed.....
You're right Wobbly Box it is really difficult to cut through the Sikaflex, with access from one side only due to the end of the Alloy sheet being firmly stuck in the recess on the back of the rail I've come to the conclusion that I'm leaving the rail in place.
I had a good look at the rail this weekend and having checked the wood along the top edge of the rail by putting the screws part way in and giving them a good tug with a pair of pliers. I have refitted the screws along the top edge and run a bead of Sikaflex between the roof and the top edge of the awning rail. This leaves me with the vertical part of the rail firmly bonded to the alloy sheet and absolutely no wood to screw it to, as all the wood which formed the end of the side panel has disappeared into dust, rotten wood.
The cause of the problem appears to be that there was zero or very little sealant between the front plastic panel and the end of the side panel. So any water that got through, simply rotted away the wooden rail which was only about 25 mm by 25mm to start with. I'm going to abrade the plastic panel and clean the underside of the alloy sheet apply Sikaflex to a new wooden upright and between the plastic and alloy and pull it all together with a lot of stainless screws. Then put a bead of Sikaflex between the plastic front panel and the awning rail.
If the rail is as you say impossible to come off then that sounds like your best option. Counter sink the the rail screw holes so the screw head sits slightly below flush and apply some Sikaflex over the screw head.
Also pump Sikaflex into the screw hole before putting in the screw.
I've managed to rebuild the corner of the caravan from the inside and then re-bond (with Sikaflex) and screw the awning rail on to the side of the van. It doesn't look very pretty at the moment but it hasn't leaked at all over the last few days of rain. Just need to finish off the inside and tidy up the sealant along the edge of the rail.
When I worked for a boat building company the only way we found to break the seal of sikaflex was with a very very hot spatula constantly heated and forced into the join, and it's dam hard work when its stuck well and truly!
Yes Sikaflex is a permanent fix/bond right enough.
The main problem with the rail Sikaflexed to the aluminium sheeting was that I couldn't get a blade of any sort between the two, On the one side of the rail, it was directly in contact with the sheeting i.e. no gap for even a Stanley knife blade. On the other side of the rail it just overlapped the end of the sheet which was well bonded by Sikaflex within the hollowed out rear surface of the rail. Trying to pull them apart enough to get any sort of blade between them, required so much force that the distortion to the aluminium sheet and rail was excessive.
I agree with Moppetsdad.Get a paint scraper and a butane gas heat gun and heat the scraper.It is a night mare of a stuff to get off and i cant find anything on you tube that shows how to take it off bar this..and its on a pick up which had a cab removed...Clicky thing