Interior, what caulk was used around windows

[bmklawt]

Some of my windows and the tail lights leak, I can see from the interior where water is leaking through gaps in the caulk where it has pulled away from the tail lights and window frame.
The caulk is yellow in color and still soft and pliable it is also still sticky if you dig into it, but it has shrunk and pulled away from the window frames.
I am trying to find out what it is so I can get it off and re-caulk around the windows while I have some interior panels off, I am also assuming Vulkem would be the correct caulk to replace it with.

Any help I can get on this will be greatly appreciated.

[HappyCampeur]

I am 99.99% it is some sort of urethane (Vulkem is) so just take off the old sealant, clean the substrates as much as possible and replace with new Vulkem (or Trempro same thing but different branding) and you have compatibility issues. ie:Silicone and urethane don't go well together.

[silverleeper]

Hi Bruce, Caulk on the inside of the window is not a good way to stop leaks. I'm not positive but I don't think there should be caulk on the inside of the frame. Fix all leaks from the outside to prevent your floor from roting out. Here is a list of popular sealants.

[Torii]

My Tradewind has a polyurethane sealant on most of the inside seams. It is white in color and was applied by the factory in 1975 when it was made. I have yet to find a spot where this sealant has failed. In some areas where I have removed exterior panels I have re-sealed the interior seams using a Sikaflex product I got at a local lumber yard. It seems to work perfectly and looks just like the factory stuff.

Sealing from the outside is what most people do because they don't have accsess to the inside of the seams. That works and there are several products that work well. (parbond, acrylR, gutterseal etc.) checkout vintagetrailersupply

IMHO, if you have the interior panels off, it is very advantagous to seal the seams from the inside because it seals up all of the rivet holes as well as the seam. You can then seal the seam on the exterior as well.

[InsideOut]

That looks to me to be a PO's attempt to stop a leak(s). I don't think Airstream ever used visible caulk inside the trailer like shown in your picture. (on edit: per Torii's post, looks like I may be wrong) Regardless, Lee's advice of correcting the problem from the outside is sound. Your skin seams may need to be re-caulked (we used Vulkem & Sikaflex). Water leaks are tricky - even though the leak is appearing inside the trailer at the windows, it may be a leak that is entering the skins somewhere else on the exterior.

The best thing to do to make sure the leak is found, is to remove all the old sealant from the seams on the exterior with a popsicle stick (or something similar) and re-caulk all your seams & joints. There are companies that do pressure tests with bubbles to locate leaks, but on vintage trailers alot of the sealant can start to fail - so it may be harder to isolate a single failure.

Shari

[bmklawt]

I am almost positive this is factory, every rib, stringer, window, door and vent has this stuff on it, all the caulk seems to be good accept the front and back window, tail lights and where some screws have rusted like on the dip edge over door. The interior seams do not have caulk on them, I will caulk those as well as long as I'm in there.

I do plan on resealing all the seams on the exterior but I thought I should fix what needs fixin while the interior panels are out.