Teflon tape on flare fittings

[JoeG]

Also teflon tape softens and breaks down when it comes in contact with any kind of solvent or petroleum based fluid ...........Use the blue paste used on natural gas and oil fittings if you feel it necessary to use anything...But flare fittings in most cases are not very forgiving if the flare is bad as Belair said...

[TDW]

Threads on a flare fitting do nothing as far as sealing. The seal comes from the taper of the pipe or tubing being pressed into the sealing surface of the fitting. A thread lube is a good idea on the threads just to prevent galling and make the flare nut tighten down a little easier.

[JoeG]

OK --In a ****quick fix ****if the flare is just having a problem seating against the face of the nipple fitting and unless the flare itself is not split or chipped--wiping some blue paste on & around the **face** NOT threads of the nipple fitting usually stops the leak----------I've had to make ***temporary repairs*** in a pinch ------Replacing a worn flare fitting is the proper procedure for a permanent repair--------save teflon for the faucet. ......

[Keith Tedford]

The nut doesn't seal, it just holds the flare surfaces tightly together so that they don't leak. Bad flare, bad leak. It's not a pipe thread.

[Steve Shauger]

Teflon tape was not originally used, and is not needed in a flare fitting application.

[69 Post Sedan]

Plus if the tape tears and gets into a line it could plug the line. I was priming a motor I rebuilt. I used teflon tape on the threads for the oil gauge. At first I wasn't getting a pressure reading on the gauge. When I removed the gauge, the tape was covering the small hole for the gauge.