Fuel line thread sealant

[Paul Lee]

What works best for fuel line thread sealant.
Teflon, RTV-silicone?

[Richard Riley]

On 22 Feb 2004 00:31:39 -0800, (Paul Lee)
wrote:

:What works best for fuel line thread sealant.
:Teflon, RTV-silicone?

Either Fuelube or EZ turn
http://www.aircraftspruce.com/catalog/cspages/ezturnlube.php

Teflon tape and RTV are very bad in a fuel syste. Teflon tape, if it
is wrapped beyond the threads, can tear off and clog the system. RTV
swells and becomes very soft when exposed to fuel or oil.

[Cy Galley]

NEVER EVER use Teflon tape. regular Pipe dope with Teflon powder works well
but the very best is Loctite PST.

--
Cy Galley, TC - Chair, Emergency Aircraft Repair, Oshkosh
Editor, EAA Safety Programs
or

Always looking for articles for Sport Pilot


"Paul Lee" > wrote in message
om...
> What works best for fuel line thread sealant.
> Teflon, RTV-silicone?

[Paul Lee]

Just found "TFE Pipe Thread Sealant w/Teflon" that claims to
be good for all threads, fuels, wide range of temperatures.

Anybody tried that?

Richard Riley > wrote in message >...
> On 22 Feb 2004 00:31:39 -0800, (Paul Lee)
> wrote:
>
> :What works best for fuel line thread sealant.
> :Teflon, RTV-silicone?
>
> Either Fuelube or EZ turn
> http://www.aircraftspruce.com/catalog/cspages/ezturnlube.php
>
> Teflon tape and RTV are very bad in a fuel syste. Teflon tape, if it
> is wrapped beyond the threads, can tear off and clog the system. RTV
> swells and becomes very soft when exposed to fuel or oil.

[Paul Lee]

Cy,

Just looked up Loctite PST and it says "Not recommended for use on
plastic piping". For example I have a plastic fuel level sensor going
into aluminum
tank hole piece embeded in epoxy. It seems that the "TFE Pipe Thread
Sealant
w/Teflon" fits the bill better on that one.

"Cy Galley" > wrote in message news:<sG6_b.381795$na.571587@attbi_s04>...
> NEVER EVER use Teflon tape. regular Pipe dope with Teflon powder works well
> but the very best is Loctite PST.
>
> --
> Cy Galley, TC - Chair, Emergency Aircraft Repair, Oshkosh
> Editor, EAA Safety Programs
> or
>
> Always looking for articles for Sport Pilot
>
>
> "Paul Lee" > wrote in message
> om...
> > What works best for fuel line thread sealant.
> > Teflon, RTV-silicone?

[Cy Galley]

Good catch. I just don't like plastic for fuel or brake lines. I
understand wanting to use a clear plastic tube for a gage but with all the
aromatics they put in car and Avgas, plastic may not hold up. We had an new
RV-4 with plastic brake lines at Oshkosh that melted a hole in his plastic
brake due to the long taxi distance at Oshkosh. Fortunately there wasn't
much wind that day.

"Paul Lee" > wrote in message
om...
> Cy,
>
> Just looked up Loctite PST and it says "Not recommended for use on
> plastic piping". For example I have a plastic fuel level sensor going
> into aluminum
> tank hole piece embeded in epoxy. It seems that the "TFE Pipe Thread
> Sealant
> w/Teflon" fits the bill better on that one.
>
> "Cy Galley" > wrote in message
news:<sG6_b.381795$na.571587@attbi_s04>...
> > NEVER EVER use Teflon tape. regular Pipe dope with Teflon powder works
well
> > but the very best is Loctite PST.
> >
> > --
> > Cy Galley, TC - Chair, Emergency Aircraft Repair, Oshkosh
> > Editor, EAA Safety Programs
> > or
> >
> > Always looking for articles for Sport Pilot
> >
> >
> > "Paul Lee" > wrote in message
> > om...
> > > What works best for fuel line thread sealant.
> > > Teflon, RTV-silicone?

[optics student]

I imaging ProSeal would work will, but you would only need to mix up a tiny
amount. How about TiteSeal? You can
get it from Aircraft Spruce and it does not harden with age.
"Paul Lee" > wrote in message
om...
> What works best for fuel line thread sealant.
> Teflon, RTV-silicone?

[Dan Thomas]

Somebody mentioned FueLube, and that's what should be used. A workable
alternative is the old Aviation Form-A-Gasket, in the nonhardening
form, made by Permatex now. Silicones of any sort, or Teflon tapes,
are OUT.
Most guys are way too worried about fuel leaks. We're talking about
almost negligible pressure here, even in a pump system, and sealants
like FueLube will easily prevent leaking. In a past life I ran an air
brake rebuilding shop, and was forever getting back valves and
compressors with split pipe ports caused by beefy mechanics torquing
up the NPT fittings "just to make sure it don't leak." I found that
with a bit of sealant, the fitting wouldn't leak when little more than
finger-tight. This was with pressures ranging from 15 psi (coolant
systems) to 150 psi ( high-end air brakes). Even 1200 psi hydraulics
didn't need much tightening. Tight enough to prevent its shaking out
is enough, and vast amounts of goopy, dangerous sealants are totally
unnecessary.

Dan