On a dark and stormy night....all this happened, more or less....in the early 80s, Van prescribed 2-3 coats of brushed-on PR1005L over Proseal before the rear baffle popped on. Then, 2-3 coats of sloshed PR1005L concentrated on the read baffle. In 1983,I followed the prescription up to the last bit. After I popped on the baffles, no leaks. So, I did not slosh. But there was plenty of PR1005L in the tanks on the ribs and stiffeners.
I began flying my 4 in June 1986. The years went by. For about 12-15 years, I used 92 octane no-lead auto in the right tank, about 5-6 tanks for every 100 LL left tank. The plugs were gorgeous and clean, and never any hesitation on power-up. But, about 2004, the right tank began to stain, and the stain grew into a damp weep over the years....So, I switched back to 100LL on both sides. In about 2011, the left started a little stain and then rapidly (over a year or so) started weeping. Not sure, but I suspect the aromatics in the auto fuel were just a little more aggressive versus the proseal....
In any event, this past winter, I finally bit the bullet and finished what I started by sloshing the baffles. I know the Randolph story, but it's not buna. I have never heard any criticism of PR1005L, and not because everyone who used it is dead. Certainly, I have seen no evidence of peeling/delamination in my tanks, and the Weep No More guys seem to use a similar product over proseal on their Mooney tanks. So, in 2012, I sloshed with PR 1005L. 1 pint total, 1/2 in each tank in two separate coats. I kept constant pressure air feed in my fuel pick-up and vent lines and deem this an absolutely worthwhile precaution since it keeps the syrup from blocking anything. Result? no visible blockage; no fuel flow restrictions at any power setting; no evidence of flake into gascolator or visible thru fillers (the new coat is sticking just like the 30 year old coats); and.....dry, clean tanks...whew!
What this is not: an engineering study or recommendation or warranty or anything like that. No doubt, someone can kill himself with this stuff, and, if enough people use it, someone will. But, seems to be working for me, and certainly was the prescription, oh, so many years ago.
Here is a link to the product: http://www.ppg.com/coatings/aerospace/sealants1/pr_1005L.pdf
MTCents, John N95JF
A screaming comes across the sky. - Thomas Pynchon
I began flying my 4 in June 1986. The years went by. For about 12-15 years, I used 92 octane no-lead auto in the right tank, about 5-6 tanks for every 100 LL left tank. The plugs were gorgeous and clean, and never any hesitation on power-up. But, about 2004, the right tank began to stain, and the stain grew into a damp weep over the years....So, I switched back to 100LL on both sides. In about 2011, the left started a little stain and then rapidly (over a year or so) started weeping. Not sure, but I suspect the aromatics in the auto fuel were just a little more aggressive versus the proseal....
In any event, this past winter, I finally bit the bullet and finished what I started by sloshing the baffles. I know the Randolph story, but it's not buna. I have never heard any criticism of PR1005L, and not because everyone who used it is dead. Certainly, I have seen no evidence of peeling/delamination in my tanks, and the Weep No More guys seem to use a similar product over proseal on their Mooney tanks. So, in 2012, I sloshed with PR 1005L. 1 pint total, 1/2 in each tank in two separate coats. I kept constant pressure air feed in my fuel pick-up and vent lines and deem this an absolutely worthwhile precaution since it keeps the syrup from blocking anything. Result? no visible blockage; no fuel flow restrictions at any power setting; no evidence of flake into gascolator or visible thru fillers (the new coat is sticking just like the 30 year old coats); and.....dry, clean tanks...whew!
What this is not: an engineering study or recommendation or warranty or anything like that. No doubt, someone can kill himself with this stuff, and, if enough people use it, someone will. But, seems to be working for me, and certainly was the prescription, oh, so many years ago.
Here is a link to the product: http://www.ppg.com/coatings/aerospace/sealants1/pr_1005L.pdf
MTCents, John N95JF
A screaming comes across the sky. - Thomas Pynchon