Thread sealer for fuel system?

[needabronco]

I'm having 'issues' sealing my NPT fittings in my fuel system, I can't seem to get my return fuel lines to stay sealed, nor can I seal my accumulator fittings. They are seaping just a little bit and are wet, but not dripping. I've used thread tape, and the paste, but I'm not have success.

Any ideas?

 

[broncorick]

Thread sealer shouldn't be needed if flared correctly. It is the smooth fit of the flare that seals. Check for burs, bad flare, etc.

 

[Madgyver]

Brush on thread sealant or what we call "dope" in the trade is what I use.

3 tightly wraps of teflon tape should do the trick for most NPT fittings.
It may be the dies if you're cutting the thread yourself. I had the same problem running pipe for diesel fuel and I found out it was bad cutting dies...

 

[broncnaz]

Usually you dont want any sealer on any fuel fittings but if you use it just make sure it doesnt get into the fuel system could cause you all kinds of problems especailly with EFI. I'd use the tape type and tighten those fittings down. If tape doesnt do it then I'd say you have bad fittings. Shouldnt even need sealant.

 

[Madgyver]

The standard is to leave the first thread exposed when using any type of sealant..

 

[blubuckaroo]

A lot of thread sealers won't hold up to gasoline. I've had that happen and have used the old Permatex #2 non hardening sealant.

 

[Madgyver]

Permatex #2 is also considered a thread sealer..

Also remember that teflon is there the aid in tightening the fitting or pipe nipple without galling the threads..

 

[jghflys]

I use this stuff.

http://www.aircraftspruce.com/catalog/cspages/ezturnlube.php

It's used on aircraft fittings and to lube valves. It works pretty well. Permatex # 2 is also a favorite and more available.

James

 

[bronco italiano]

That aircraftspruce stuff looks like the military stuff I use for sealing type 1 vw cases together. BI