Teflon ape on fuel line fittings

I might be just full of bull, but I seem to remember reading somewhere that you don't use teflon tape on fuel line fittings, and the reason escapes me. Do you think this is only rubbish?

I would never use teflon tape on fuel fittings. If it breaks off (including during removal) it can plug up small orifices in the fuel system including the carb.

A good sealant (I use Loctite PST teflon sealant) is recommended.

The first thing one should do is establish what type of fitting you are referring to. Inverted flare as well as AN flared type fittings require no sealant.

The only fitting that does is pipe type thread which is a tapered thread. There are several different acceptable sealants that can be used. The primary concern with the tape is it sometimes leaves strands behind that can find there way to the fuel system/ carburetor

I use liquid Teflon sealer on all my pipe thread fittings. Just a dab on the clean dry threads and you will be leak free. You can get it from any parts store or even the hardware stores carry it.

Gus

If you were to use teflon tape, it needs to be the yellow type which is resistant to fuel

Yellow Teflon tape is designed for natural gas and propane lines, not gasoline.

White for liquid gasoline or diesel
OP, do NOT use any sealant on any AN fitting other than the NPT ends

Oh no my bad sry. I’ve beem wrong all these years

Good thing you never had a 'splosion!

Per the following there really isn't a "CLEAN" answer regarding the use of the yellow tape. Seems there are different types depending on the usage. NICE!!!!

YELLOW TEFLON TAPE ARTICLE

GM used white Teflon tape for years on Q-Jet fuel inlets, not as a sealant, but as a friction reducer, it allowed the flare nut to be tightened sufficiently without rounding the flats. Paul

For flare fittings, I always used a little grease on the back of the tube flare, and on the nut flare and threads.

anti seize is my preferred stuff to use.

If GM had flared the fuel line carb end properly they wouldn't have needed to do that

white Teflon turns clear in gas and when a little piece gits in a needle and seat you can't see it and will cause you to cuss a lot while trying to figure out why it still floods.

I wasn't going to start the debate but seriously doubt they used the tape

I've been using the yellow on fuel (gasoline) fittings for many years, including adding to an AN fitting that leaked a bit.

It may not have been made for gasoline but I've never an issue with it failing yet.

My roll of yellow is so old there's no label on it anymore, but it was whatever was at Home Depot at the time.

I remember a cartoon called the GRAPE Ape but Teflon Ape is one I've never heard of.

Oh, it's a similar character, only a very slippery one! So I forgot to check the title, but remember nobody likes a wise guy.....just joking, I deserve that.

FYI, The Teflon APE is the one that gets loose in your fuel system or starts a fire under the hood

It's easy to change it.....sheesh.

I have heard or read that if the teflon tape is needed to prevent leaks then the fittings are not machined properly. I have no control over how the store bought fittings are machined...I just do what I can to avoid leaks.

Are we talking flared lines?
If so, I never had a leak on fuel or brake lines since I learned how to form my own. (decades ago)
Never even considered tape on them.
No experience with the pipe threads on automotive projects.

Option one:
https://www.aircraftspruce.com/catalog/cspages/ezturnlube.php?clickkey=9406
option two:
https://www.aircraftspruce.com/catalog/cspages/sealube.php
the best for last, option three:
https://www.aircraftspruce.com/catalog/cspages/tite-seal-04-03925.php

I have all 3 and some gazilla, niel seal for pipe threads, ez turn for lubing fuel valves and AN threads, seal lube AN threads