Advice on resealing a leaky high top van?

[EricI]

Hi all,

My '06 E250 high-top converted van is driving me nuts. I've tried at least four times to reseal this top, with no luck. It rained the other day and I've got water pooling up in the front corners, which then drips down near the front of the headliner.

Anyone have any luck resealing a leaky top? Mine is fiberglass from Mobility Works (former wheelchair van). I have been using 3M 4000UV marine sealer at the recommendation of a shop called Automotive Sealers (seems like they would know what to use). I cannot for the life of me figure out where water is getting in. I have so much sealant on it and I can't see any cracks.

I am wondering if I am making the mistake of trying to put sealer over the top of the exisiting sealer/caulk, and that's my problem.

I'd love any advice you all can give me. I'm close to wanting to sell this van it's so frustrating.

[SMB123]

Don't know where you are but I use a damp tester that plumbers use on a variety of stuff. The best bet it to catch it in the act. If your area gets a lot of rain may have to wait.

Ideally - you could start with a dry van with negative damp tests then wet it and isolate source. But otherwise - the good ones also make a faster oscillation sound when more water present so you can narrow in on where most coming from.

Could be hairline or seal or any number of things. Keep Occum's razor in mind - any windows nearby? Some butyl strip can fix that very effectively (very hard to work with but effective).

[N147JK]

Originally Posted by EricI

I am wondering if I am making the mistake of trying to put sealer over the top of the exisiting sealer/caulk, and that's my problem.

I have found that "flooding" a drying sealant on, such as silicone or caulk, hoping it stops a leak usually doesn't work well or lasts long.

Once you find the source, recommend a non-drying, tried-and-true sealer like butyl. Just a small amount of butyl in the right places is a clean way to seal water out. It's old school stuff, but it still works great!

[Twoxentrix]

Couple pic's of the top would help.

When you refer to the front headliner do you mean above the front seat area? is it possible it's coming through the top corners of the front windshield? Any rust visible up there - or in the rain gutters?
On a dark night, you may try holding a bright flashlight inside the van pointed towards the top (and move it around) while you have someone outside on a ladder looking down to see if they can spot any light coming through the top? If its hairline crack you probably will not see anything.

[BlackSheep]

My '04 Clubwagon has a 20" aerodynamic top from Fiberine. I assume it was installed when the van was new or nearly new - thus the top is now about 20 years old. I also have water leaking into the van. Depending on how I park it can pool up in the front, over the cab.



I tried to contact Fiberine but they did not return my voice nor email messages. In talking with a guy, he suggested using Automotive Seam Sealer. I have purchased a bunch of it - probably much more than I'll need (I didn't want to risk running out). My approach is to dig out the existing sealant, paint anything that needs to be painted, clean it then run a bead of the seam sealer.



My biggest problem is the Fiama awning. I can't access the drip rail under the awning and to remove the awning I have to completely remove the wood liner inside the high top.



I am in the middle of a pretty extensive rebuild of the interior, having completely rebuilt the electrical system and added a new floor which was not originally on my list. I risk not getting everything done already so pulling the interior of the high top is very unlikely to happen.


I may risk sealing the three sides and as far as I can manage up to and under the awning and hope for the best.

[larrie]

It would be best to remove/dig out as much of the old caulk as possible. Caulking compounds from different manufactures or different types do not always adhere to each other thus allowing the leak to continue.

[1der]

BlackSheep - I sent you a PM re awning. Did not want to mess up this thread.

[wanderers]

A few years ago I had a windshield with a "Yukon star" replaced and I was getting water on the headliner in the middle near the rear-view mirror. At first it seemed to be from around the topper but since I had just had the windshield replaced I had the installer replace the glass again and that solved it. I'm not sure how you can check the windshield for leaks, but that could be the problem. I had an old Ford Escort that developed a leaky windshield years after the windshield had been replaced too, so the cause isn't always that apparent. I don't think replaced windshields are sealed as well as the factory installed. Good luck, these leaks can be really tricky to track down.

Roger

[doublevan2]

Possibly see if your local garage or windshield installer can do a "smoke test" around the supposed leak area - or maybe you could do an air gun pressure test around the windshield where a suspected leak is ?

[SteelheadJones]

I’ve heard soap spray and compressed air can reveal bubbles where the leak is.