X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 23 Mar 2009 12:59:09 -0400 Message-ID: X-Original-Return-Path: Received: from rv-out-0506.google.com ([209.85.198.234] verified) by logan.com (CommuniGate Pro SMTP 5.2.13) with ESMTP id 3555815 for lml@lancaironline.net; Sun, 22 Mar 2009 18:04:49 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.198.234; envelope-from=vonjet@gmail.com Received: by rv-out-0506.google.com with SMTP id g9so1516611rvb.7 for ; Sun, 22 Mar 2009 15:04:13 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=fBlyvuNvVAU8MGwlopzd/2hANNflGbJ2kiPZjz3sA8eYvJc64ANTs14Pf8qwBg+1Rq xgBatRUuLmYZQguff7kELM4d77jclUGVlExy/5LW0lQfILch+8X8ZWIaXrVNfQgSrp2u +17ubtCKz6NDVi8BGEHnqqZ51BSvhzADVOBxY= MIME-Version: 1.0 Received: by 10.141.133.14 with SMTP id k14mr1927460rvn.119.1237759453267; Sun, 22 Mar 2009 15:04:13 -0700 (PDT) In-Reply-To: References: X-Original-Date: Sun, 22 Mar 2009 15:04:13 -0700 X-Original-Message-ID: Subject: Re: [LML] Re: Fuel selector Valve question From: Bryan Wullner X-Original-To: Lancair Mailing List Content-Type: multipart/alternative; boundary=000e0cd22f848789660465bc54d3 --000e0cd22f848789660465bc54d3 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Thanks everyone for your comments. I will stick with the stock set up. I do have an auto fill system in place for the header. I have 2 sensors (high and low) in the header and they activate the wing transfer pumps to keep the header full. I was just worried that if my header line clogged for any reason I would not be able to get fuel to from another source (wings). On Sun, Mar 22, 2009 at 1:13 PM, Gary Casey wrote: > Bryan, > I'm afraid the setup you mention would be troublesome. I don't know if a > 1/4 line is adequate or not, so I'll pass on that. Generally it is > undesirable to connect both tanks together in a low-wing plane, and this > might be especially true of one with low dihedral. The problem is that even > a small difference in fuel level could result, as the fuel level gets low, > in one tank unporting, allowing air to enter the system. As soon as air > gets in the other tank will likely stop feeding entirely, shutting off the > fuel supply. You could probably feed off both down to some level, but that > level might be 1/2, and then there would be no reliable way to get the rest > of the fuel out. How do high-planes get by with it? They run each line > separately down to a common sump at the bottom of the plane. The difference > in pressure would have to be larger than the head of fuel from top to > bottom, about 4 feet or more.. In a low wing plane there is no vertical > height available. If you had a "three-way" valve that could select > R-L-H-off it could work, I suppose.. > Gary Casey > > ------------------------------ > > > I want to run this idea I have past the group. > My current set-up is 1/4" lines coming from my wing tanks to the my header. > Then a 3/8" line feeds my engine. In this configuration I can only feed > the engine from Header only. This is the stock Lancair 320 fuel system. > > I would like to be able to run my engine off my wing tanks if needed but I > don't want to re-plumb the wings with 3/8" lines. Can I connect the 1/4" > wing tank lines into a "T" with a 3/8" exit and run the line to the selector > valve? Essentially the wings would not be able to be selected but they > would feed at the same time equally. > Would this idea work? And if so what type of Andair valve would I need? > One with just a Left/Right/OFF And I would have them custom engrave the > bezel to read Wings/Header/OFF > > Thanks > Bryan > > > --000e0cd22f848789660465bc54d3 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Thanks everyone for your comments. I will stick with the stock set up. =A0I= do have an auto fill system in place for the header. I have 2 sensors (hig= h and low) in the header and they activate the wing transfer pumps to keep = the header full. I was just worried that if my header line clogged for any = reason I would not be able to get fuel to from another source (wings). =A0<= div>


On Sun, Mar 22, 2009 at 1= :13 PM, Gary Casey <casey.gary@yahoo.com> wrote:
Bryan,
I'm afraid the se= tup you mention would be troublesome. =A0I don't know if a 1/4 line is = adequate or not, so I'll pass on that. =A0Generally it is undesirable t= o connect both tanks together in a low-wing plane, and this might be especi= ally true of one with low dihedral. =A0The problem is that even a small dif= ference in fuel level could result, as the fuel level gets low, in one tank= unporting, allowing air to enter the system. =A0As soon as air gets in the= other tank will likely stop feeding entirely, shutting off the fuel supply= .=A0=A0You could probably feed off both down to some level, but that level = might be 1/2, and then there would be no reliable way to get the rest of th= e fuel out.=A0=A0How do high-planes get by with it? =A0They run each line s= eparately down to a common sump at the bottom of the plane. =A0The difference in pressure would have = to be larger than the head of fuel from top to bottom, about 4 feet or more= .. =A0In a low wing plane there is no vertical height available. =A0If you = had a "three-way" valve that could select R-L-H-off it could work= , I suppose..
Gary Casey



I want to run this idea I have past the gr= oup.

My current set-up is 1/4" lines coming from my= wing tanks to the my header. =A0Then a 3/8" line feeds my engine. =A0= In this configuration I can only feed the engine from Header only. This is = the stock Lancair 320 fuel system.

I would like to be able to run my engine off my wing ta= nks if needed but I don't want to re-plumb the wings with 3/8" lin= es. =A0Can I connect the 1/4" wing tank lines into a "T" wit= h a 3/8" exit and run the line to the selector valve? =A0Essentially t= he wings would not be able to be selected but they would feed at the same t= ime equally.=A0
Would this idea work? =A0And if so what type of Andair valve would I n= eed? =A0One with just a Left/Right/OFF =A0And I would have them custom engr= ave the bezel to read Wings/Header/OFF

Thanks
Bryan



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