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devinevision
05-17-2010, 03:39 PM
I have a 2001 31/24 KB that I bought used about a year ago. The forward section roof has leaked a good portion of that time. We caulked the daylights out of every seam and skylight and it held for a few months but recently it started leaking like crazy again. I climbed on the roof today and I could lift the center seam that is covered by a long rubber strip forward of the first skylight up with my fingers. The rubber strip is still glued securely to one side of the aluminum sheeting but does not stick at all to the other. The sheet that it has stuck to is beginning to de-laminate from what I suppose to be the foam core. Obviously I've got to stick this mess back together. Any suggestions on what adhesive to use or any thing else helpful? Thanks

Dan:new_all_c

ShrimpBurrito
05-17-2010, 03:57 PM
I had the same exact problem when I first bought our new-to-us 2000 2720SL. I slid a little 3M 5200 under the aluminum to adhere them back together. You can buy 5200 at most boat/marine stores, sold in both a full-sized caulking tube and a smaller toothpaste-like tube. Like all 3M products, it is not cheap.

For the rubber/plastic strip, I pulled the old one entirely off and bought a new one from the factory. Once I received it, I rounded off the corners of both ends to make for a more secure adhesion. The strip had a self adhesive backing, but is designed to be used with a 3M primer for maximum adhesion-- I'm pretty sure it is called 3M 94 Tape Primer. It is not cheap either, nor easy to find -- best to look online. Once the 3M 5200 adhesive fully cured (24 hrs), I spread a little 94 primer with a paint brush, pulled back a few inches of the protective paper from the self-adhesive backing on the back of the plastic strip, and carefully started laying the strip down on the roof. Just do a few inches at a time, removing the protective paper as you go. You only get one shot, so take your time.

The repair has held up without any problems thus far, looking just as good today as the day I repaired it, and that was 3 years ago.

Dave

Wavery
05-17-2010, 05:04 PM
Slight correction........

3M 5200 will skin-over and start to cure in 24hrs. After 7-days, it will cure enough to work with safely. It takes 90-days for 5200 to fully cure. Once it is cured, it is the devil to remove so be sure that this is the path that you want to take. IMHO, 5200 is a permanent attachment. If it ever has to be removed for some reason?????????? the removal process will likely cause damage.

Another good solution is eterna-bond:
http://www.bestmaterials.com/SearchResult.aspx?CategoryID=1021

Again, it's pricey, permanent and not real attractive. However, it has been proven over and over again to be very effective in permanently solving roof leak issues.

IMHO, 5200 is the more attractive of the 2 (if used properly) but the eterna-bond may be the better solution in this particular case. You will never have to touch it again......but you will have to look at it....;)

ShrimpBurrito
05-17-2010, 06:56 PM
I have heard good things about the eterna bond, but don't really know much about it. If you don't want to use the 5200, you could also just use a thin layer of polyurethane construction adhesive, or 3M 4200, which is very similar to 5200, just not as permanent and way easier to remove if necessary.

Dave

Wavery
05-17-2010, 07:22 PM
Don't get me wrong, IMHO, 3M 5200 would be a very good choice. It's just important to know that it is irreversible. It's also important to know that 5200 cleans up with mineral spirits. Mineral spirits can turn one messy job into one very nicely finished job. Just don't over do it.

Eternabond is a very thick, very sticky material that is used for commercial roofing. I have never heard anyone that has regretted using it.

The roof of our apt building is actually done with the same material.
http://img.photobucket.com/albums/v333/wkavery/4-20-07003.jpg

devinevision
05-18-2010, 06:20 AM
good to know similar problems have had happy solutions. I was going to go with 3m 4200 for its removability but I hope removing it will never be necessary. I don't know if ordering a new rubber strip is going to happen...we plan on a big vacation in a couple of weeks but we are going to the desert southwest. I don't think rain will be to much of a problem.

rumbleweed
05-18-2010, 07:26 AM
Make sure you remove the old caulk an inch or two into the area where is is securely attached. Clean the area to be caulked real well with alcohol. If the caulk is lose, water carrying dirt has gotten under it.

brulaz
05-18-2010, 07:49 AM
Dave,
Getting back to the plastic strips you ordered from the factory with the self-adhesive backing. Do you know if these are the same glossy plastic strips used in the latest TrailManors to cover seams? Did you caulk the sides of the plastic strips as well, or just rely on the self-adhesive backing and tape primer?

I ask because our leaks occurred where caulk had pulled away from the side of the plastic strips. And obviously the glue under the strips wasn't stopping anything.

ShrimpBurrito
05-18-2010, 09:22 AM
Clean the area to be caulked real well with alcohol.

I actually prefer to use something like acetone or mineral spirits. Since the purpose of doing this step is to clean the surface, remove residue, etc., you need a solvent, and alcohol is not a particularly good one, especially compared to acetone or mineral spirits. I usually test the solvent on a small non-important area to make sure it doesn't cause problems (like remove paint) before I go all crazy and start applying it everywhere. In this instance, it worked great.

Dave,
Getting back to the plastic strips you ordered from the factory with the self-adhesive backing. Do you know if these are the same glossy plastic strips used in the latest TrailManors to cover seams? Did you caulk the sides of the plastic strips as well, or just rely on the self-adhesive backing and tape primer?

I ask because our leaks occurred where caulk had pulled away from the side of the plastic strips. And obviously the glue under the strips wasn't stopping anything.

I don't know if they are the same since I have not seen a new TM in years -- they are the smooth quasi-shiny plastic strips about 1" - 1.5" wide that run down the center of the roof over the seam from the front of the trailer to the back. I don't see them anywhere else on the TM.

No, I did not caulk the sides of the plastic strips. I just glued the underlying metal together, applied the 94 primer, and laid down the plastic strip. It is still down there rock solid.

Perhaps the factory didn't apply the 94 primer.....but they were the ones to tell me about it when I ordered the strips.

Dave

brulaz
05-18-2010, 04:35 PM
I don't know if they are the same since I have not seen a new TM in years -- they are the smooth quasi-shiny plastic strips about 1" - 1.5" wide that run down the center of the roof over the seam from the front of the trailer to the back. I don't see them anywhere else on the TM.

Sounds similar. Next time I get a leak, I'll pry up the plastic strip and take a look at what's underneath. Your method sounds very neat, with no caulk at the edges, especially as I'm really messy with caulk.

On the Elkmont roof there are three long strips running the length of the roof, one in the center and one on each side abutting the painted Al corner piece. All of them come (poorly) caulked. And there's other pieces on the sides and ends.