by sonex1363 » Mon May 05, 2014 10:29 am
Yet another option is Permatex Aviation Form-A-Gasket No. 3 which is (ironically) sold in local automotive stores like Autozone, and in spite of the "gasket" name, is also intended for NPT thread sealing. From the label: "Sealant approved for use in aviation as well as automotive applications. For use on screw-thread connections. Pressure-resistant and leakproof to high octane gasoline, hot and cold water, antifreeze, kerosene, and other fluids."
Costs about 6 bucks for a large-ish bottle that should last forever.
I haven't put the final sealant on any fuel thread connections yet, so I can't comment on its effectiveness, but I was planning on using either this, or possibly the Loctite 567 which has worked for me in other applications.