An excellent thread sealant

[rockyrim]

It's great to see a lot of building going on. For you builders yet to reach the plumbing stages,
I wanted to recommend Permatex Aviation FORM-A-GASKET Sealant Liquid
3H 80019. I've waited to see if this was going to be a good product, and I haven't had the first seep, at the beginning, at annual, nothing. And it's still soft, which of course is what you want. For those of us who would like to build again and do some things differently, that's not one of them. There are dozens or hundreds available, glad I picked good one. I hope this is a useful tip. (Resists lube oils, antifreeze, aviation fuel)

Denise and Rocky Whitman
Series 7 912S
Austin

[DanB]

Thanks for the info Rocky,
Did you use this on both the fuel and brake lines?

[rockyrim]

Hi Dan,
I sure did, now that you mention it, I wasn't thinkin' about brake lines.
And my brakes are as tight as ever. I have not bled them since completion.
And I used it on all fuel NPTs and I never have a fuel smell when I open the
cockpit.

Rocky

[RandyL]

It's great to see a lot of building going on. For you builders yet to reach the plumbing stages,
I wanted to recommend Permatex Aviation FORM-A-GASKET Sealant Liquid
3H 80019. I've waited to see if this was going to be a good product, and I haven't had the first seep, at the beginning, at annual, nothing.

Rocky, what spcifically did you use this on, AN pipe thread fittings or AN b-nuts?

[rockyrim]

Tapered pipe threads only. NPT

[RandyL]

Roger. I've always used Permatex 14A "teflon pipe thread sealant", works well too.

[Slyfox]

I would be very cautious with that sealer, it is very sticky and you may not get the fittings all the way on like you want. With that said, I use the High performance Tread Sealant from permatex, it's white and slippery, in other words, the threads will go on all the way. I'm sure the stuff you mentioned will work great, but like I said, make sure the parts go together all the way. I think if I had troubles getting something to not leak, I would use it.

[rockyrim]

PRODUCT DESCRIPTION S.I.N.: 834-300
Permatex Aviation Form-A-Gasket No. 3 Sealant is a dark
reddish brown, viscous liquid with a characteristic alcoholic
odor. It is a slow drying, liquid that changes to a pliable, tacky
film through solvent evaporation. It seals close fitting parts,
machined surfaces and threaded connections in industrial,
aircraft, marine and automotive applications.
PRODUCT BENEFITS
• For close tolerance flanges
• Slow drying
• Flexible setting
• Withstands pressures to 5000 psi
TYPICAL APPLICATIONS
• Solid gasket dressing
• Close fitting machined surfaces
• Threaded connections
• Aviation engines
• Marine engines

The technical data sheets indicate that you want to avoid PTFE sealants
in aviation fuels. While teflon is great for many applications,it will do little more than lubricate the threads while makin' them up for others. While having the benefit of making up tens of thousands of fittings over way too many years at DuPont I would say that sticky pipe dope the way to go also.

[darinh]

What is the problem with PTFE thread sealants? I use a Loctite brand PTFE sealer and have had zero problems with it in all applications I have used it (fuel & brakes). In fact, I originally used the permatex stuff (not the same as listed in this post but an alcohol based thread sealer) and had 4 leaks that needed fixing. So far with the Loctite PTFE sealant everything is tight as a whistle.

[rockyrim]

Permatex High Performance
Thread Sealant
AAM Revised 08/04
NOT FOR PRODUCT SPECIFICATIONS.
THE TECHNICAL DATA CONTAINED HEREIN ARE INTENDED AS REFERENCE ONLY.
PLEASE CONTACT PERMATEX, INC., TECHNICAL SERVICE DEPARTMENT FOR ASSISTANCE AND RECOMMENDATIONS FOR YOUR SPECIFIC APPLICATION.
PERMATEX, INC., HARTFORD SQUARE NORTH, 10 COLUMBUS BOULEVARD, HARTFORD, CT 06106 PHONE – (1-87PERMATEX)
PRODUCT DESCRIPTION S.I.N.: 834-300
Permatex High Performance Thread Sealant is formulated for
fast, responsive curing on metal pipe threads and fittings. This
sealant is a smooth, white paste-like compound with PTFE
that controls lubricity to assist assembly and torque tightening.
PermatexHigh Performance Thread Sealant replaces Teflon
tape or pipe dopes. It cures rapidly to withstand 10,000 PSI
within 24 hours. Prevents galling and protects mated
threaded surfaces from rust and corrosion. The product cures
when confined in the absence of air between close fitting
metal surfaces. This product is not recommended for use
on plastic piping. NSF White Book registered.
PRODUCT BENEFITS
• Quick fixture time
• Prevents galling and corrosion
• Controlled strength
• Temperature and solvent resistance
• Immediate low pressure sealing
• Contains PTFE
TYPICAL APPLICATIONS
• Stainless steel fittings
• Head bolts into through holes
• Oil PSI sending units/sensors
• Oil and coolant lines
• Hydraulic line fittings
• Brake fittings
• Transmission fluid fittings
• PTO fittings
• Air conditioning fittings

Here is the TDS for one of Permatex' highest quaility PTFE based thread compounds. The Aviation sealant I posted was suitable for aviation fuels
and aircraft, the example I posted above makes no mention of aviation fuels
or fuels of any kind, or aviation quality. While we don't have to adhere to aviation quality, at $4.33 I think could squeeze up a notch.