RWolf99@aol.com wrote:
>
>.........
>
> My question is whether there will ever be air downstream of the Facet pump.
> Or will the line between the pump and the header tank inlet always have fuel
> in it?
>
In my 235, I have the Facet pumps under the seats and two polyurethane tubes
which carry the fuel from the pumps to the header tank.  These tubes go up the
left side of the radio stack.

There is a picture on my web page.   http://home.comcast.net/~rbelshe/  I looks
like one tube, but actually there are two, one in front of the other.

When a tank runs dry, there is a mixture of air and fuel coming up the tubes
with very obvious bubbles.  They catch the eye quickly because they are moving
fast.

When the wing tank is not empty and I shut off a pump, after about 20 seconds I
can see the fuel go down as air from the header tank replaces the fuel in the
line.

I use a small kitchen timer connected to the intercom to remind me to pump fuel,
and have a 10 minute automatic shutoff to stop the pumps.  In 500 hr. I have had
to replace just one Facet pump, so the system must work OK.

Bob Belshe
N19BJ