leaky threaded fuel fittings

[Dan Barlow]

I have a low pressure fuel pump that is part of the conversion of going from a old style sbc to a carbed LT1. It is leaking around the thread.to the screw on filter. Should I tighten the thing more to crush the threads a little or is there a good gas.proof thread tape or sealer.

[Barry Donovan]

I used pro seal once.
made a fuel return n the back of a carb, first try. needs nothing, been a year.

there is silicones everywhere, but the gas worthy ones take awhile to hunt down.

pro seal company also makes super glue. I guess that is not the same as crazy glue. Cannot remember how I found it.. simply worked.

the type of seal is used in aviation tanks, but that is holy crap expensive. I knew one existed, they still have one for cheap.

[BigBlockMopar]

I'm of the believe that threadsealer is to be used as an added security/safety measure, not to cure an actual happening leakage.
The actual sealing should be taken care of the fitting clamping the line against the opposite flange.

Of course, in the rare cases it might occur... I can be corrected if proven wrong...

[DanStokes]

Dan - could you send a pic of the junction in question? Between me and Blulightning I'm sure we can come up with the answer. Generally there's no reason to use thread sealant as the threads are not where the seal is designed to take place (unless it's a tapered pipe fitting (NPT) - not likely from your description). Bob works for Swagelok and he can likely fix you up with the GROOVY solution.

Dan

[squirrel]

like Dan says, without seeing exactly what you're talking about, we can't give you a good suggestion....if it's a Quadrajet, they used two different types of seals on the fitting that retains the filter. The early ones used a gasket "outside" the threads, the later ones used a gasket on the end of the fitting "inside" the threads.

[Dan Barlow]

I"m worthless on pics but what I have is a Mr. Gasket low pressure external electrical fuel pump. ( 5-7 psi i think ) It has a fuel filter that screws on it. Thats where its leaking. I'll just tighten it some more. If that doesn't work I'll give Barry's idea a try. I agree that it shouldn't need a sealer. I've never needed one before on brass fittings.

[Dan Barlow]

It's been rainy here, cranked it down some more, seems to have stopped.

[rightpedal]

In a pinch J&B Weld will work as a thread sealer. You also have the benefit of a thread locker, but the down side is the thread lock. Cranking down filter casings always scares me.

I will pose the question again.... Is there a fuel use thread sealant? like on NPT fittings.

Steve

[DanStokes]

I use Rectorseal. Or as it's known in the plumbing trade (used to be one) Rectumseal. It kicks butt but it WILL make a mess all over your hands.

Dan

[anotheridiot]

slicktite by locktite made for stainless steel fittings. any teflon based non hardening high pressure sealant will work.

[yellomalibu]

On NPT fittings, I use teflon tape - being sure to start on the second thread so none of it goes into the fuel system.

[oj]

For pipethreads i use the ARP sealant, been using it for nearly 20 years and have yet to have a leak.

[MR P-BODY]

Pipe threads you use teflon tape or paste... (its actually a lube to
pull the threads tight)... pipe is the only thread you use it on.. if
you have a double flair you tighten it only(the double flair is actually
a little springy if made right) so when you tighten it, it will seal, compression
fittings go on dry(you can lube the threads on the nuts if you want)
... 35 years in the fuel lab at Chrysler

[DanStokes]

Mr. P is, of course, correct. That's what I was trying to get across but you said it more simply.

Dan

[Ron Ward]

In a pinch J&B Weld will work as a thread sealer. You also have the benefit of a thread locker, but the down side is the thread lock. Cranking down filter casings always scares me.

I will pose the question again.... Is there a fuel use thread sealant? like on NPT fittings.

Steve

#2 Permatex. Non-hardening and pliable. Good stuff!