Fuel Leak Teflon Tape?

[Lamadogg]

Asking for a friend — no really! . Teflon tape used to seal threads in fuel line fitting onto carb. After several months — car mostly sitting — leak reappears. I know teflon tape is compatible with gas but is there a more resilient or effective material alternative? Thanks in advance for any suggestions.

 

[Don Frelier]

The threads aren't what makes the seal.
It's the flared fitting on the end which makes a metal to metal seal.
You don't want bits of tape in your carb.
I'd look for a new fuel line and needle and seat.

 

[pnora]

Some carbs have a fitting the flare nut seats into. I would use tape as a last resort. If it is the fitting there should be a seal between the fitting and carb . I would replace that first. If it is the flare look for cracks in the tube. If ok either fix the line or replace the fitting.

 

[1967coronet]

What brand of carb is it ?
Some use a soft metal/aluminum washer between the carb body and fuel inlet fitting.

 

[hunt2elk]

I never ever use tape on gas line threads. Same reason you are not supposed to use Teflon tape on LP/natural gas piping in your house. A small thread of it can get into the line and cause the valve to stick open.

 

[Don Frelier]

Please no mean comments about my hairy knuckles.

 

[moparwacko]

View attachment 1628414
Please no mean comments about my hairy knuckles.

 

[Lamadogg]

What brand of carb is it ?
Some use a soft metal/aluminum washer between the carb body and fuel inlet fitting.

It’s on a ‘67 Corvette w/3 x 2 barrel set-up — same carbs used on 440 6-pack (for purposes of including in forum).

 

[bobsgtx]

40 years of working on hydraulic systems we only used thread sealant/dope and only on pipe/ tapered threads. The only time I used teflon tape was on old or cut too deep threads to try and build up. Sometimes it work sometimes not. All manufacturers would void warranty if they found teflon tape anywhere.

 

[hdwrench]

the company we used to assemble for specified on blueprint locktite 567 on all threaded connections . no teflon tape ever , anywhere on there product . it is a thread sealant and i admit works well , i don’t ever remember a leak at a thread during use . if your experiencing a leak at a tapered fitting (an3 / an4 style ….) that is a different problem.
p.s. an afterthought- this sealant is said to have an anitseeze technology, as a thread lubricant during assembly. especially if your using stainless steel it lubes the thread during assembly preventing galling….

 

[dadsbee]

the company we used to assemble for specified on blueprint locktite 567 on all threaded connections . no teflon tape ever , anywhere on there product . it is a thread sealant and i admit works well , i don’t ever remember a leak at a thread during use . if your experiencing a leak at a tapered fitting (an3 / an4 style ….) that is a different problem.

View attachment 1628473

Agreed, I use PST592. Haven't had a fitting leak on anything, mainly aviation fuel and hydraulics, in 31 years.