[sglynn]

Is Permatex Thread Sealant good to use for nuts/threads on my fuel lines? It says it is for use on metal and fuel, oil, hydraulic fluid. I got it to use on the nuts that hold my fuel return line and vent line to the blue fittings that exit the inboard rib of the tanks? And I thought I might use in on the flop tube nut to the blue fitting also. Is this the right stuff to be using for these purposes? I figured it would help seal, and hold the nut from vibrating off. Right? Or is this a product to steer clear of for airplanes? It says its major content is Polyglycol Dimethacrylate Ester.

 

[DanH]

Steve,
Use sealant on male NPT fittings and plugs (tapered pipe thread). The threads on flare fittings only hold the tube flare in contact with the seat on the fitting. The threads themselves do no sealing. You can use a little thread lube on them if you want, but most folks don't bother.