Teflon tape on flare fittings

[firstgenaddict]

I see lots of resto's with teflon tape on the flare fittings... fuel lines and sometimes brake lines... can anyone explain this to me? I have never seen teflon tape cure a flare fitting leak...
Also do the judges dock points for it?

[Belair62]

Makes no sense. A bad flare is a bad flare.

[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.

[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. http://www.yenko.net/ubbthreads/images/graemlins/ooo.gif

[JoeG]

OK http://www.yenko.net/ubbthreads/images/graemlins/grin.gif--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. ......

[Motion Camaro]

<font color="blue">I've seen a locking compound on threads so they do not back off. Not for sealing though. </font>

[bkhpah]

It just makes me laugh every time I see it...BKH

[micky69396]

Its about as common as trunk weatherstrip installed the wrong way. That dont work either.

[firstgenaddict]

Or upside down cowl induction seals? http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[L78steve]

Teflon tape is helpful on the threads of bleeders.You can vacumme bleed w/o pulling air down the threads.

[YENKO DEUCE REGISTRY]

[ QUOTE ]
It just makes me laugh every time I see it...BKH

[/ QUOTE ]

Ditto! Along with GM labels with bar codes still affixed to various parts, http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[juliosz]

The only time I've seen teflon tape or thread sealer used on flare fittings is when someone uses stainless steel lines. As most of you know, they can be a bear to initially seat and seal without drips. I think many folks do it out of frustration. The slick setup for stainless fuel lines is a copper insert that goes inside the flare. A mechanic who retired from a Caddy dealer after many years had a bunch in his tool box. I don't know if you can still get them anywhere but they sure made sealing up a 427/435 vette with stainless fuel lines pretty easy. http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

[Belair62]

Maybe if they made the fuel lines sets in the U.S instead of China,Hong Kong or Mexico they would seal better ?

[firstgenaddict]

I had a problem getting the lines to seal on the 69 Z... I had to seat all the fittings separately anf then install the whole setup... they leaked like a seive before...

[TDW]

[ QUOTE ]
Maybe if they made the fuel lines sets in the U.S instead of China,Hong Kong or Mexico they would seal better ?

[/ QUOTE ]

Without a doubt they would be better. You wouldn't believe what I am going through buying ONLY American made parts for the Nomad Gasser project. The only thing I HAD to buy imported were the ET 10 spoke wheels, and it killed me to do that.

[firstgenaddict]

The inside taper on the tubes seems to be the problem... they are misformed or not fully formed.
The only way I could get them to seat was to take them one at a time and snug it down... then rotate the line 360 deg a few times and it would get looser... snug again... and repeat a few times... then I tightened them up on the car... viola no leaks! (you may be able to use a dbl flare tool and reform the inside tapers)

[P.J.]

[ QUOTE ]
Maybe if they made the fuel lines sets in the U.S instead of China,Hong Kong or Mexico they would seal better ?

[/ QUOTE ]

As some of you know the reason that the stainless wont seat properly is that its too hard. They should heat treat the metal tube so that it softens it to the sam RC as the steel ones.It would then seat great and look great.
DA-----HHH.
PJ