VegasJen

one point that needs to be emphasized now that we've determined that you can use it on the threads is that it will not cure your leak. yes it's safe to use but since the threads aren't doing any of the sealing then it's not going to solve your problem. you still need to find out why the compression seal isn't holding. keep us posted.

MikeC

I don't have it con my fuel line but have used it for a holley carb I used to run, I put it on the threads of the flare nut...... It did stop the small dribble of fuel that I have.

I have never run into problems running teflon tap e on a fuel line. But a Flare fitting should not require any sealant. The pressure the nut puts on the flare should seal everything of, if it doesn't the flare was not done correctly.

Matt Gruber

even if the flare nuts' threads are sealed perfectly to the carb, i guarantee it will still leak.(unless of course the flare seals)

does anyone else understand why?
this is worth 2 points on the Auto-shop 101 final exam :yesnod:

The Dude

1. No.
2. Yes.
3. N/A.
4. N/A.

I use it as a thread lubricant on the Holley fuel fitting. Flare fittings don't require anything on the threads to prevent leaks. It makes it easier--for me--to torque the fitting properly and it helps delay the inevitable galling that sometimes happens with metal-to-metal joints that are frequently torqued down and remived. Just make sure not to put any tape over the last couple or three threads on the nut or you run the risk of getting teflon threads in the system. In fact, Holley recommends this practice.


[Modified by The Dude, 9:30 AM 8/8/2002]

BB wowbagger

What about using a small O ring made from gasolinesafe rubber and put it between the Flare and the opposite part..That may work..
Like,putting the O ring "in" the flare :cheers:

VegasJen

of course, the threads aren't and never were designed to be a sealing surface. the soft metal of the flare is designed to crush and conform to create the seal. it's very likely that the leak he is experiencing right now is because of a split in the seam of the tubing. it's just a thin wall carbon steel tube, not like stainless steel or anything. overcompression will cause it to split where the seam was rolled. i've split my share of brake line tubes and that is basically the same stuff. :rolleyes:

Fevre

Of course if the flare nut creates a seal with the outside lip of the fitting then it won't leak either as long as the nut threads are sealed. Of course if the the pipe makes a seal with the inside of the nut then it won't leak either. Of course if the pressure outside the carb is higher then in the fuel bowl it won't leak. Of course if the.......

Ah, some laws are made to broken. :)

NHvette

There are two cases where I can see a teflon tape "appear" to seal a
leaky flare fitting. First, If the flare has a groove - allowing it to leak, and the
nut has a good seal to the backside of the flare - the leak would only be
allow to go past the threads (not the pipe). Thus, enough teflon tape
to successfully fill the voids in the threads of the nut would "appear" to
seal the leak. Effectively, it would. Actually, it was bubba'd.

Second, a grooved flare is leaky, and the owner tries some teflon tape.
After wrapping the tape around the threads of the nut, the threads
become somewhat lubricated. The easier turning threads allow the nut to
be tightened further - thus sealing the grooved flare by higher applied pressure. Actually, this IS sealed - but the owner may not be as lucky next time.

Lastly, the "yellow" teflon tape is intriguing. Since it was purchased at a Lowes
home repair store, I am inclined to believe that it is made for sealing of
LP/natural gas (not gasoline) in black iron threaded piping. I'm also inclined
to believe that a product that seals natural gas would work with gasoline,
assuming the teflon does not break down chemically with gasoline.

Teflon tape is indispensible for putting air hoses and air tool fittings together. :yesnod:
:seeya

Fevre

Dave

I read the disk container your store it in and it states 'gasoline' right on it, along with other things, so it should be good for non-comp fitting like a barbed hose adaptor.

Chris

mrvette

clutch, what you said is all true, but it's the steel lines and steel fittings that kill the product, mating into a brass fitting into an aluminum housing over the years corrodes all to hell, and the steel line would rather twist into pieces rather than give it up off the nut....
no amount of tapes or compounds will absolutely cure that situation...they most often won't come apart after even 5 years...let lone more....

Yeh, I can use a large wrench hold the damm fitting in thehousing, and twist the line to a kinked mess turning the flare nut loose...
hell with it, anymore, I just cut the damn lines and use hose...forgetabout it...unless it's high pressure like fuel injection....course the AN fitting don't have that problem...
steel on steel flare into brass....yeh, really smart design...duh....

GENE