Does anybody know if it is? Installing fuel system tomorrow.Got the tape on hand don't wanta make an unecessary trip to the parts store for thread sealer if there's no need...

 

It has always worked for me, have used it on diesel, gas, hyd oil, av gas, has always worked. just make sure the fittings are dry when you apply, I have had diesel make a mess of it during application if not clean and dry. my .02

 

Good dealI won't waste a trip then...

 

diesel will eat teflon !! you need to use a sealant that can handle fuels, chemicals and stuff. I foret what it's called but, you can get it in the plumbing section of a hardware store.

 

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Gotta go to town anyways I'll pick upthe rightthread sealer thanks.

 

There is a common misconseption about teflon tape that it actually helps sealing, and this, simply, is not true. Teflon tape is intended for NPT (national pipe tread aka normal pipe thread) fittings and taps. These threads are tapered, and the threads themselves do the sealing. The addition of teflon tape simply lubricates these threads so they get deep enough to seal. Thread sealant (pipe dope) is nothing more than teflon paste with silicone in it. It is best used for water or natural gas pipes because it will lubricate and add an extra margin of safety for sealing if the fittings/pipes were not tightened enough. Pipe dope will not get a better seal on gasoline because silicone will be eaten by any type of fuel, as well teflon, eventually. Although i've never used the permatex, I'm sure it is a teflon paste mixed with some type of chemical resistant sealant, and should work in the same manner as pipe dope on fuel fittings.

Teflon tape for compression, flanged, or flared fittings is simply not required. The sealing is done by other methods (compression fitting, flange, or flare).

The key to use it correctly, is to wrap the fitting or pipe as little as is required for the tape to hold itself, and to wrap it correctly before hand. Clean, dry threads, and the tape wrapped so that it wraps tighter while you thread it is essential. Other than that, make sure the fitting/pipe is tight enough, and you should be good!

 

Yeah that makes sense with the tapered threads. And why you gotta be careful when tightening if you want things lined up a certain way to not go too far cause backing out is gonna make it leak. And also why I would always replace NPT fittings if I took something apartrather than re-use them. But everyone says use thead sealer so I will. They didn't have the above kind anywhere I went. Ended up getting some hi temp permatex item# 765-2648 didn;t say anything about diesel resistant, no-one had anything that dd, but it did say "NOTE: hi temp thread sealant seals threaded metal fittings on hydraulic, pneumatic, fuel, and cooling systems. it is not recomended for plastics or rubber" good enough..