Help...my pro-seal has disintegrated

Mark33 · #1 10-05-2016, 08:44 PM

I have been flying my -7 for a little over a year now. About a month ago I put it in the hangar with full fuel. Yesterday, I was doing a preflight and noticed a lot of blue on the bottom of one of my wings. I ended up pulling the tank off to do a full inspection of the problem. I had previously installed two fairly large inspection plates on the back side of the tanks to enlarge the small holes in the ribs so that it would take on fuel faster and to install a piece of tubing for my return line for my EFII systems so that the warm return fuel would dump into the outside bay. I'm baffled at what I found. The pro-seal has basically disengage....it's just a gummy mess. What's even stranger is that it's only disintegrated along the bottom seam of the tank and along the bottom forth of the sides of the inspection panels that I installed and around the bottom screws that's holding the plates. It's like there was some kind of contamination in the fuel that settled into the bottom of the tank and has destroyed the pro-seal. The upper three forth of the tank and plates are just fine. Has anyone ever heard of this? What's even stranger is that I filled both tanks at the same time but the other tank isn't showing in signs of a leak. So, with all this being said, I'm afraid that this tank has been compromised to a point that I'm going to have to install a new one. The problem that I have right now is that I don't have the time to build a new one. I know I've seen a previous post or two of someone that builds tanks. I've searched the forum but I can't seem to locate that information. Can someone provide me with the contact information of the person that builds tanks? Can I possibly buy a prebuilt one from Vans?

Thanks for any help.

170 driver · #2 10-06-2016, 05:38 AM

Mine did the same, left tank, It seems the blue dye in the fuel after evaporating from a seep, softens the sealer, I started off making the access holes and patching up the leaks first with no good results. I had to remove the whole rear baffle and reseal and reinstall. I ended up removing and reinstalling the tank 3 times, it doesn't leak now. What a PITA!

Flying again! · #3 10-06-2016, 06:49 AM

I had small leaks I chased for years. Each time I thought I had them fixed they would start leaking after 6-8 months. I finally pulled both tanks and sent them to Weep No More (http://www.weepnomorellc.com/). The did a great job! External paint was not hurt, and turn around was good. They have a 7 year leak free warranty.

Lot less hassle and cheaper than building or buying new tanks which may leak anyway.

TJ

DanH · #4 10-06-2016, 06:53 AM

Yes, we've seen it before.

http://www.vansairforce.com/communit...d.php?t=122300

David-aviator · #5 10-06-2016, 08:14 AM

And the beat goes on...how come it happens with some airplanes and not others?

Same with blisters...its like a **** shoot in gambling joint, even factory built tanks are not immune.

Mixture matters, mixture doesn't matter....I've built 4 tanks, so far, knock on wood, they don't leak or show blisters. The only ones that did were built by Vans.

What was the difference? I don't know except I used more pro-seal, was mixed up by hand in normal room temperature.

But don't hold your breath, they could start leaking tomorrow.

Mark33 · #6 10-06-2016, 09:43 AM

Thanks for the replays guys! I thought maybe I had done something wrong or had maybe gotten some contaminated gas, but it looks like other people have experienced the exact same thing. I'll clean everything up and re-pro-seal everything and roll the dice one more time...and hopefully I'll be golden after that. What I did notice, after removing the large inspection covers, was that the inside of the tank looked good. I clicked on the link that Dan provided and one of the replys to that post was that if the pro-seal is exposed to a fuel moist environment and it is also exposed to an oxygen rich environment, that is where the breakdown occurs. That would make sense because on the inside of the tanks, even if the fuel level was low, there's enough vapors present to displace the oxygen molecules. If there's a small leak somewhere and fuel is able to keep the pro-seal moist (and the outside of the tanks are exposed to plenty of oxygen), then this is where the breakdown begins. Thanks again for all the replays guys.

Mark

Neal Trombley · #7 10-08-2016, 07:38 AM

Possible catalyst issues?