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My cured Pro-Seal has turned to goo!

She said (summary) after having been responsible for this product in various adjusted forms, for more than a decade, she had never found any reversion of properly mixed and cured product exposed to any avgas.

Trouble is, the Flamemaster guy said the same thing.
 
What else could they say?

Trouble is, the Flamemaster guy said the same thing.

Funny - they all probably will/do - - -which is good- people could just send in the goo for analysis. The trouble is the time lag between purchase-application and occurrence, not to mention serial numbers, batch numbers and the like.

The unused tanks example would be relatively pristine.

Maybe it is so rare that the customer will get a complementary (and fresh) container for their trouble. :D

Randolph Engineering sent me a brand new pair of aviator sunglasses after mine broke (2 weeks ago). They were a gift from my boom-operator uncle sometime in the 70's. Likely part of their original USAF contract. Ya never know. They even send back the original unscratched lenses.
 
Does anyone's track record match DeSoto's?

I've gotten to speak with DeSoto engineers in the past. I'm not a chemist or ChemE but it still leaves an impression when speaking with someone that stands out in their field. I did learn a serious case-in-point. There is original application Desoto sealant in some B52s that is over a half century old. While those wings were almost always continuously wet with jet fuel (JP8?), there's also a lot of flex in them. This was before they buttered they sealing surfaces; fillets and top coats. Doesn't mean the original is necessarily better but that fact still impressive, at least to me.

My tanks are sealed with ProSeal. It will still be there when I'm not.
 
I'm not sure what brand it was Walt and I no longer have the can but I bought it direct from Vans, in good faith, along with the pre-made fuel pickup tubes. It was shipped separately, some time after the wing kit, so that the use by date would not be expired.

I've just opened up the second tank access panel and it too is like goo inside, both the sealant in the fuel tank and on the pickup tube that was ready made.

There must be other RVs flying around in this condition. The only reason I found out about the internal state was due to opening up the tank for the SB. It seems this type of sealant is not really fit for purpose if it can fail so readily without any indication of the cause.

25 years ago, the sealant being sold by Van’s was the trademark name Proseal.
That is likely why it is the common reference for tank sealant within the RV building community.
 
Which one

PPG/PRC Desoto 890 is my go-to or 1422

Walt,

What would cause you to opt for one of these over the other?

Ralph
RV-10
Empennage complete
Currently working on extended range tanks
 
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The 890 is my go-to with the 1422 as a good alternative. If I remember correctly the 890 has improved corrosion resistance.
 
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