Fuel Line Thread Sealant- Best ??

[ArticiferTom]

Looking for recommendation . Found Teflon allows connectors in tank and fuel pumps to twist from alignment  easily . I often see what looks like blue or red color sealant on plugs and other brass when new . What is it ?  Or would Indian Head Shellac dried to parts work .

[Bloo]

I believe that stuff is a form of Loctite.

 

If you are going to try Indian head, put it on wet. It is brittle when dry.

 

It is slippery when wet, so don't overtighten and break something. I would be extremely hesitant to use Indian Head on anything near a fuel system today. There is too much alcohol in the gas.

 

I speak of pipe threads here. Other fittings probably don't seal on the threads.

 

I use teflon paste, as I don't want the tape anywhere near a fuel system. If a fitting moves, I redo it. I figure if there is any tension in the tubing, it might unscrew later from vibration.

Edited August 28, 2018 by Bloo (see edit history)

[Bhigdog]

Aviation Permatex. Works very well and lasts a long time..............Bob

[Frank DuVal]

Gasoila, made for the application!  

 

http://www.gasoila.com/

 

Available on line or at most plumbing supply houses. Hardening and non-hardening. They even make one specifically for alcohol blends.

 

http://www.gasoila.com/products/pipe-thread-sealants/gasoila-e-seal-thread-sealant.html

[Curti]

Never use Teflon tape on fuel systems. Little pieces of it have been found blocking passages in carburetors .

[edinmass]

11 minutes ago, Curti said:

Never use Teflon tape on fuel systems. Little pieces of it have been found blocking passages in carburetors .

 

 

Please repeat ten thousand times................NEVER,NEVER,NEVER!

[PFitz]

14 minutes ago, Curti said:

Never use Teflon tape on fuel systems. Little pieces of it have been found blocking passages in carburetors .

 

Same for oil lines, too !!!!!!!!!!

 

Paul

[auburnseeker]

I've been using a red almost purple colored stuff I buy at NAPA.  It works great,  never hardens and is good for pretty much everything from antifreeze to fuel systems.  I put my 36 Chrysler back together after rebuilding the engine and nothing that had that on the surface leaked.  I've used it on lots of stuff since and it have been very pleased with it.  I used to use the regular permatex, but it's not good for Antifreeze applications.  This way I only need one can of stuff in the shop.  The only draw back I have found is it's very stringy when you apply it so you get buggers everywhere if you aren't careful.  

[54vicky]

it should never leak if using right fittings and flares.if leaks redo period.50-60 year old at least that old do not leak

[joe_padavano]

3 minutes ago, 54vicky said:

it should never leak if using right fittings and flares.if leaks redo period.50-60 year old at least that old do not leak

 

I'm assuming the OP is talking about sealing NPT threads, not inverted flare fittings.

[54vicky]

I only use brass pipe fittings on fuel pump carb etc. never had need to use sealant if leaked I usually just replace fitting cheaper than a fire

Edited September 9, 2018 by 54vicky
spelling (see edit history)

[Guest]

Have never used any sealant on any brass fitting in 60+ years.  Only had one leak (cross threaded, no idea how that happened).  Iron pipe plugs (oil pan, transmission and differential) always dry and never had a leak.

[carbking]

For those that insist on using sealants on fuel fittings, we make an excellent selection of carburetor rebuilding kits.

 

Jon

[ArticiferTom]

Yes, talking the threaded brass to alloy of fuel pumps and steel of tank bung . Also brass to brass as my plan is to add a shutoff safety at tank elbow .

    Jon , assume you are a nothing guy or tape guy .  Tom

 

Edited August 31, 2018 by ArticiferTom (see edit history)

[edinmass]

Many people overlook the obvious advantage of teflon tape and many other sealeants not only on fule lines but gasket surfaces. I have made tens of thousands of dollars in labor repairing cars that have plugged oil, fuel, air, and other passageways and surfaces. I am also a BIG fan of fuel injection cleaner you pour into the gas tank. It does a great job of cleaning all the junk in the tank, then fortunately it goes in the fuel filter, carburetor, fuel pump, and often damages other components, I absolutely love the stuff........it has paid for several of my hobby cars. Now.....shall we talk about dry gas? I'm also a BIG fan of that stuff also!  ? ?

Edited August 31, 2018 by edinmass (see edit history)

[auburnseeker]

Never Never NEVER Use that Blue RTV.  Besides it looks herendous hanging out all the gasket surfaces it seems to come loose and get into everything.  I have a nicely rebuilt detailed engine in my 40 Ford and the guy that did the fuel suystem over before me, loved the crap on the gasket surfaces and it looks herendous. 

My Hudson had nice blue Buggers stuck in the carbs. Rebuilt them and it runs wonderful after cleaning them all out.  

[carbking]

8 hours ago, ArticiferTom said:

Yes, talking the threaded brass to alloy of fuel pumps and steel of tank bung . Also brass to brass as my plan is to add a shutoff safety at tank elbow .

    Jon , assume you are a nothing guy or tape guy .  Tom

 

Tape? Tape?

 

Oh yes, once I thought I had found a legitimate use for Teflon tape. My Dad used to love to mow grass, and as he grew older his eyesight deteriorated somewhat; and I had just set out over 100 saplings. So I tied the tape (it comes in a number of bright colors) onto the saplings so Dad could see them easier. It worked for about 2 mowings, and then the deer ate the tape.

 

So I still have yet to find a legitimate use for Teflon tape.  Might be able to use it for ribbons on Christmas presents. Book markers? It must be good for something?

 

On the serious side: if the fittings are clean, started properly, and not overtightened; THEY WON'T LEAK!

 

Jon.

[PFitz]

6 hours ago, auburnseeker said:

Never Never NEVER Use that Blue RTV.  Besides it looks herendous hanging out all the gasket surfaces it seems to come loose and get into everything.  I have a nicely rebuilt detailed engine in my 40 Ford and the guy that did the fuel suystem over before me, loved the crap on the gasket surfaces and it looks herendous. 

My Hudson had nice blue Buggers stuck in the carbs. Rebuilt them and it runs wonderful after cleaning them all out.  

Any color RTV. I've found far too much of chunks of the stuff stuck in oil pump screens, and the oil pump feed pipes of systems the screens have rotted away. !!!!

 

Paul

[PFitz]

18 minutes ago, carbking said:

Tape? Tape?

 

Oh yes, once I thought I had found a legitimate use for Teflon tape. My Dad used to love to mow grass, and as he grew older his eyesight deteriorated somewhat; and I had just set out over 100 saplings. So I tied the tape (it comes in a number of bright colors) onto the saplings so Dad could see them easier. It worked for about 2 mowings, and then the deer ate the tape.

 

So I still have yet to find a legitimate use for Teflon tape.  Might be able to use it for ribbons on Christmas presents. Book markers? It must be good for something?

 

On the serious side: if the fittings are clean, started properly, and not overtightened; THEY WON'T LEAK!

 

Jon.

This !

A good connection for fuel or oil  doesn't need anything else. Save the Teflon tape for those it was meant to be used by,...  plumbers.  If it leaks, don't throw the wrong modern fix at it that it was never meant for.  Don't kick the problem down the road, find out why the original design isn't working.

 

Paul

Edited August 31, 2018 by PFitz (see edit history)

[auburnseeker]

Well sometimes a little sealant might be necessary as we aren't talking about fresh parts in some cases.  Many have had who knows how many hands and wrenches on them so nicks and stuff have been formed where regardless of how tight you tighten it,  you will never distort the fitting enough to conform to the discrepancy.

Some fittings also require being connected at certain angles where if you have to tighten it a hair more dry,  then you will have to go all the way around.  I'm pretty sure I didn't have another 360 degrees turn left in that fitting before it bottomed out or I couldn't turn the 3/4 inch wrench anymore where the wrench wouldn't strip, not to mention if it's into pot metal,  like a fuel pump or such you might crack the female fitting cast in it. 

Edited August 31, 2018 by auburnseeker (see edit history)

[carbking]

1 hour ago, auburnseeker said:

Well sometimes a little sealant might be necessary as we aren't talking about fresh parts in some cases.  Many have had who knows how many hands and wrenches on them so nicks and stuff have been formed where regardless of how tight you tighten it,  you will never distort the fitting enough to conform to the discrepancy.

Some fittings also require being connected at certain angles where if you have to tighten it a hair more dry,  then you will have to go all the way around.  I'm pretty sure I didn't have another 360 degrees turn left in that fitting before it bottomed out or I couldn't turn the 3/4 inch wrench anymore where the wrench wouldn't strip, not to mention if it's into pot metal,  like a fuel pump or such you might crack the female fitting cast in it. 

 

Exactly why teflon should NEVER be used. Teflon is a wonderful lubricant. Over the years I have thrown away a number carburetor castings which were cracked, and still had teflon thread residue. New male fittings were available for these, off the shelf. I understand that occasionally, especially on older vehicles, new fittings MIGHT not be available off the shelf. Some 40 plus years ago, we paid a tool and die maker to fabricate special tools to allow us to machine new inverted flare fittings. And I shutter to think how much I have tied up in special thread taps and dies for various non-standard threads. Not impossible, and sometimes a bit of money spend on tooling saves a bunch of money. Not that hard to acquire new fittings.

 

Jon.

[auburnseeker]

I wasn't talking about teflon.  I use that purplish stuff I mentioned above.  Works excellent, doesn't harden and I have never used so much that it would get into the system, just on the threads. 

[Frank DuVal]

Sounds like Permatex High Tack. Is it, or does it have a NAPA brand label?

 

A trick to any thread sealant (and I no longer use PTFE tape on fuel for reasons mentioned) is to leave the first thread of NPT fittings dry (bare metal. No sealant). This usually keeps the crap out of the pipes. 

 

PTFE is a lubricant. Theory is it allows the tapered threads to mesh better, as the fitting can be  tightened more. With the results mentioned. The tape was in military stock system as anti-seize tape. 

 

Fresh brass fittings historicaly needed no sealant, but newer stuff is another story. Or maybe it is just the “low bid” issue of stuff we get at work. ?

Edited September 2, 2018 by Frank DuVal (see edit history)