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Old October 21st 08, 08:55 PM posted to rec.aviation.homebuilt
jerry wass
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Default Fuel System Musings, comments encouraged

wrote:
On Oct 20, 11:55 pm, flybynightkarmarepair wrote:

Anybody have anything to say about the fittings? That was my initial
interest. Should I ditch the pumps I have and just bite the bullet
and go with AN fittings per the exemplar? Do all those unions make
sense?(heavy little suckers! Think of a ball of solid brass the
diameter of a quarter for the 1/8" NPT size, and the diameter of a
Susan B. Anthony dollar for the 1/4" NPT size, and they lighten the
wallet to the tune of $13-20 per at the same time they increase empty
weight) - given that NPT fittings don't seal anyway metal-to-metal,
and you can "clock" them with SOME degree of freedom as long as
they're at least slightly more than finger tight, relying on Loctite
Pipe Sealant to keep them leak free?


AN fittings are available in aluminum. They weigh almost
nothing. Look for the blue fittings. But watch when you thjread an
aluminum pipe thread into another aluminum fitting or tank boss;
they'll grab and gall and tear the threads apart if you don't use some
decent sealant. We use Seal-Lube, Permatex Aviation Form-A-Gasket,
sometimes Loctite hydraulic sealant. Stay away from teflon tape.

Dan

And why not teflon tape???BECAUSE-it has a tendency to extrude from the
threads in a FORWARD direction,Into the fitting, depositing the stringy
little pieces in the first Carb float needle valve or metering jet they
come to..Jerry