Leak near tail light, but it's not the tail light

[adwriter73]

I have been tracking this leak for months. I used Vulkem and Parbond in every location where I thought this leak could be starting, and it's still showing up. I attached a photo and indicated in red the areas within the wall that I can feel wet insulation. What makes me think it's not the tail light is that I can feel moisture above the tail light assembly. Where else should I check?

[Minno]

How far up above the tail light are you feeling wetness? It might be wicking up from the tail light. Or might it be leaking at the window and wicking over and down. Or maybe from the banding? Puzzlement...

Kay

[ventport]

Do you have clearance lights up high on the corners?

[adwriter73]

There's a hole (for wire) at the top of the tailight assembly in the wall. I can get a finger in there an feel moisture. So, it has to be the window or the clearance lights. My guess is the window, but I can't tell how. Based on everything I've checked, there's no areas for water to get in the wall.

[adwriter73]

Originally Posted by Minno

How far up above the tail light are you feeling wetness? It might be wicking up from the tail light. Or might it be leaking at the window and wicking over and down. Or maybe from the banding? Puzzlement...

Kay

I was wondering about the banding, but how would that leak? I mean, it's just decorate trim that's riveted on, right?

[Protohyp]

I posted this a while back. maybe it helps you locate

http://www.airforums.com/forums/f142...ts-100647.html

[Minno]

Our banding was only riveted on with pop rivets, so if they're not sealed at the back, they could potentially leak. We also had a piece of banding fall off while she was still sitting in the yard being worked on. That prompted us to decide to completely re-rivet all the banding before taking her on the road. We used closed end pop rivets to do this, drilling out a few and replacing before going on to the next set. Took me most of an afternoon, but it's now all solid and sealed.
Water might also potentially travel from other areas, such as the curved area above your window. Might be a long shot, but people have had water show up on the floor that came from the roof and down a wall. Water will always seek the path of least resistence and if there's a small leak up there, it could run down the outside wall till it hits insulation to soak into. Stranger things have happened!

Kay

[barts]

In our 1971, we had problems with leaks around the taillight housing. I'd definitely make sure that the housing is thoroughly caulked. I used Alcoa aluminum gutter seal since it's a very visible (near eye height) location and that stuff leaves a nice bead if carefully done.

- Bart