Received-SPF: pass
 receiver=logan.com; client-ip=209.85.214.52; envelope-from=lehanover@gmail.com
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=mime-version:date:message-id:subject:from:to:content-type;
        b=mQg3gSlZcwI5JGp9gGfnjVVXbj0fm2YHUlIVsgVHPGlKBYsKuCZ4aauNIycxMsN+9m
         6CIiPBljcNne5Ey47rtDIY8awBFGz2N4B70jtlWX9DGbPhlV0nC3C2ZsjCvP3IX74qZF
         ToNeDZFAMO70bJbQe95yjNOzKnUBZc5ib1ghg=
MIME-Version: 1.0
Date: Mon, 24 May 2010 08:26:59 -0400
Message-ID: <AANLkTimNIdZDdjIogKAv1DaKuloLbf0uZ5TfGI8gPw__@mail.gmail.com>
Subject: Float bowl
From: Lynn Hanover <lehanover@gmail.com>
To: flyrotary@lancaironline.net
Content-Type: multipart/alternative; boundary=0015175df08a4909a1048756286d

--0015175df08a4909a1048756286d
Content-Type: text/plain; charset=ISO-8859-1

here is a picture of the fuel system, tried the scanner and the file was to
large.  Fuel must be seeping back thru the L.P. regulator and fuel pumps.
 JohnD      To soon old, to late smart, which comes a bit at a time.

Fuel can flow through a sliding vane pump. It takes a while, but the vanes
can slip out of contact with the housing, and the pump can loose its prime,
or a disconnected fuel line hanging below the fuel level in the tank can
empty the tank.


When the pump has recently made pressure, the pump will not leak through,
and this can lead to a misunderstanding. Like two sliding vane pumps in
series would have redundancy. No, not the case, one pump cannot push through
a second pump, if the second has failed. The second pump cannot pull fuel
through the first if the first has failed. Same with high pressure roller
pumps like used in fuel injected cars. Treat them like lengths of very small
diameter fuel line when they are not energized.

On the other hand it is not likely that a stopped vane style pump can flow
enough to support much more than a fast idle.

The rotary can empty the float bowl at fast idle (2,200 RPM) in less than
one minute. Even if some fuel is getting to the float bowl, I doubt that it
would be enough to show up on a Fuel/Air meter.

Lynn E. Hanover

--0015175df08a4909a1048756286d
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

<div><font face=3D"Arial" size=3D"2">here is a picture of the fuel system, =
tried the scanner and the file was to large.=A0 Fuel must be seeping back t=
hru the L.P. regulator and fuel pumps. =A0JohnD=A0=A0=A0=A0=A0 To soon old,=
 to late smart, which comes a bit at a time.</font></div>

<div><font size=3D"2"></font>=A0</div>
<div><font size=3D"2">Fuel can flow through a sliding vane pump. It takes a=
 while, but the vanes can slip out of contact with the housing, and the pum=
p can loose its prime, or a disconnected fuel line hanging below the fuel l=
evel in the tank can empty the tank.</font></div>

<p><font size=3D"2"></font>=A0</p>
<div><font size=3D"2">When the pump has recently made pressure, the pump wi=
ll not leak through, and this can lead to a misunderstanding. Like two slid=
ing vane pumps in series would have redundancy.=A0No, not the case, one pum=
p cannot push through a second pump, if the second has failed. The second p=
ump cannot pull fuel through the first if the first has failed. Same with h=
igh pressure roller pumps like used in fuel injected cars. Treat them like =
lengths of very small diameter fuel line when they are not energized.</font=
></div>

<div><font size=3D"2"></font>=A0</div>
<div><font size=3D"2">On the other hand it is not likely that a stopped van=
e style pump can flow enough to support much more than a fast idle.</font><=
/div>
<div><font size=3D"2"></font>=A0</div>
<div>The rotary can empty the float bowl at fast idle (2,200 RPM) in less t=
han one minute. Even if some fuel is getting to the float bowl, I doubt tha=
t it would be enough to show up on a Fuel/Air meter.</div>
<div>=A0</div>
<div>Lynn E. Hanover<br>=A0</div>

--0015175df08a4909a1048756286d--