X-Virus-Scanned: clean according to Sophos on Logan.com From: "Ernest Christley" Received: from nm12-vm6.access.bullet.mail.bf1.yahoo.com ([216.109.114.245] verified) by logan.com (CommuniGate Pro SMTP 6.0.10) with ESMTPS id 7240241 for flyrotary@lancaironline.net; Tue, 28 Oct 2014 11:18:24 -0400 Received-SPF: none receiver=logan.com; client-ip=216.109.114.245; envelope-from=echristley@att.net Received: from [66.196.81.157] by nm12.access.bullet.mail.bf1.yahoo.com with NNFMP; 28 Oct 2014 15:17:48 -0000 Received: from [66.196.81.152] by tm3.access.bullet.mail.bf1.yahoo.com with NNFMP; 28 Oct 2014 15:17:48 -0000 Received: from [127.0.0.1] by omp1028.access.mail.bf1.yahoo.com with NNFMP; 28 Oct 2014 15:17:48 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 665280.97333.bm@omp1028.access.mail.bf1.yahoo.com Received: (qmail 65117 invoked by uid 60001); 28 Oct 2014 15:17:47 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=att.net; s=s1024; t=1414509467; bh=PEzoWInFjrQyNJxVdiYQNwZlJuNWr1AHmc5PvMp/vCQ=; h=References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=p8hqQ18bAWy+cbiW411EgWFin13PA0Ag4Bj0W6Z+aEd1ZTDsNNa0POPtoDn8t9iXOm43oJHRb2B89J/AVG+igrlo7fUoCiNtg83HeCeUKeUaPcQ6ZqMwIa5lC/miSonZseH8b325Htg+/mTx7NC4iGFy9db6i70BROWmFAy0c8w= X-YMail-OSG: mXHltk8VM1mP2zSx1wJq9cIQz6eMqLgBRQDrcCNwsGRW1iv S7vSdNslSRKygb76L7Ef8pG8H5OJeu_LfzULJUF5ukk7nShQIiAq04sRyyZk ZUsohUgaLdaRkr42pOYD2Wmy6e4rLjPTfD6jgbv_O9vNGMsktAx3JOF.PEFC oukOUbE5UUxFHmLKLJKLCyUk7MSfumnDzBRJ6xIjfWQzkJyENY8XvkAlo85O BIdcT0cM86Ezq1IPL_9kSBlkoq7XV357K86pCmePg.HG.zst.g2dLyaAJwih UTmgxMoARtWLeKUlOKl5.QHO2ytDcsLgROdZgJIwjYnI0YgzuN84uuUVnCtD _0JgmxzAdlZrvzU75joZlM2tZOMdZQwrtM3BdJPTX6ln7TMslrB3Nqcn7JJq m2yUYKN91NIRrMHukDJnrSayjpCgrVAHHsoqHc1UjdrpayDgu6H1pghkng4K s6C9jOWnEhyLwZqyfdbeOUbSktCJPftWQK21u_M8haY4vogAriPJzKlLNp64 vyfPqUBsLKXcx4VAGjHUwRO23Jj6ZCA.PpX3jLHD.lbRN2IsWSSheRV1xnlO MBMj8QjQZh0VTFpclG27U9iRrENcbuw53aZQyxFVxqgT0FiLdR1qYj6Qugme PqUMJzb5NIa3Pn1Yt0uPdXv26A21IWQa7uDjEMwB12TtJN0aefShUt6Z5n4y jo7cEf4KmzT9x.goNKe_i8SjnoCausTWfoarCAb0mo0YWWti.nc0g5_WXz3W G824_XJ.nrKhg72GzAC6pwNx9sqlymg.E_PuKJB_ND2KCZabLoHbwjck- Received: from [70.39.176.68] by web181606.mail.ne1.yahoo.com via HTTP; Tue, 28 Oct 2014 08:17:47 PDT X-Rocket-MIMEInfo: 002.001,T3RoZXIgdGhhbiBwaHlzaWNhbCBkYW1hZ2UsIHdoaWNoIHNob3VsZCBiZSBoYW5kbGVkIGJ5IHByb3Blciwgc3RyZXNzLWZyZWUgbW91bnRpbmcsIHRoZSBvbmx5IGZhaWx1cmUgbW9kZSBJIHNlZSBpcyB0aGUgdmFsdmUgZ2V0dGluZyBzdHVjayBvbiBvbmUgdGFuayBvciB0aGUgb3RoZXIuICBUaGlzIGNhbiBiZSBoYW5kbGVkIGJ5IHRlZS1pbmcgaW50byBhbGwgc3VwcGx5IGFuZCByZXR1cm4gbGluZXMsIGFuZCBjb25uZWN0aW5nIHRoZW0gd2l0aCBhIGdhbmdlZCBtZWNoYW5pY2FsIG9uLW9mZiB2YWx2ZS4BMAEBAQE- X-Mailer: YahooMailWebService/0.8.203.733 References: Message-ID: <1414509467.45796.YahooMailNeo@web181606.mail.ne1.yahoo.com> Date: Tue, 28 Oct 2014 08:17:47 -0700 Reply-To: Ernest Christley Subject: Re: [FlyRotary] Re: electric fuel selector valves To: Rotary motors in aircraft In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-1387227393-431008167-1414509467=:45796" ---1387227393-431008167-1414509467=:45796 Content-Type: text/plain; charset=us-ascii Other than physical damage, which should be handled by proper, stress-free mounting, the only failure mode I see is the valve getting stuck on one tank or the other. This can be handled by tee-ing into all supply and return lines, and connecting them with a ganged mechanical on-off valve. If the electric valve gets stuck, pull the mechanical ones on to allow fuel to crossover. Basically, creating a Tee fitting into whichever port is open. I'm actually working on this for a Corvair installation, but this forum is the only one I've found where an idea can be discussed on its merits, instead of its compliance with standard practice. On Tuesday, October 28, 2014 10:33 AM, Mitchell Williams wrote: http://products.pollakaftermarket.com/Asset/42-159%20IS_41-revdd.pdf On Mon, Oct 27, 2014 at 6:19 PM, Stephen Izett wrote: I stand corrected. I believe Charlie is correct. >Steve Izett > > > > >On 28 Oct 2014, at 6:47 am, Charlie England wrote: >> >>On 10/27/2014 4:55 PM, Ernest Christley wrote: >> >>This is the type that I'm referring to: >>> >>> >>> >>>http://products.pollakaftermarket.com/item/fuel-selector-valves/light-truck-6-port-motor-driven-valve/42-302 >>> >>> >>> >>> >>>On Monday, October 27, 2014 5:50 PM, Ernest Christley wrote: >>> >>> >>> >>>Is anyone familiar with electric fuel selector valves as used in automotive applications. I'm trying to figure out how they operate. Do they select one line when power is applied to a solenoid type plunger, and then the other line is selected when power isn't applied? Or does a pulse of power switch them back and forth? If they maintain the currently selected tank when power is absent, it seems to me that this could remove fuel lines and a leak prone selector valve from a lot of cockpits. Furthermore, the 6 port models look like they could be plumbed easily to handle return lines. >>> >>> >>> >>> >>> The ones I've seen actually use a motor to move the valve (think screw jack), so they will remain in last position. Reading your linked item indicates that it works the same way. >> >>'Traditional' engine guys have avoided them in the past because they're plastic and they require power (and they are an automotive product, so they can't be reliable ;-) ). They are probably worth considering, but I'm seriously looking at switching to in-tank turbine pumps with automotive style PWM control; no return line needed. Then tank selection would be with a switch on the panel instead of a valve. Downside is that for total redundancy, I'd need 2 pumps in each tank. They are dirt cheap (<$20 each), but controllers are around $75 ea and switching gets pretty elaborate if there are more than 2 tanks. >> >>Charlie >> > -- Mitchell Williams OKPE, ATP/CFI/A&P/IA www.chickashawings.com of shadow and ash http://www.amazon.com/dp/B009KZGVQS ---1387227393-431008167-1414509467=:45796 Content-Type: text/html; charset=us-ascii
Other than physical damage, which should be handled by proper, stress-free mounting, the only failure mode I see is the valve getting stuck on one tank or the other.  This can be handled by tee-ing into all supply and return lines, and connecting them with a ganged mechanical on-off valve.  If the electric valve gets stuck, pull the mechanical ones on to allow fuel to crossover.  Basically, creating a Tee fitting into whichever port is open. 

I'm actually working on this for a Corvair installation, but this forum is the only one I've found where an idea can be discussed on its merits, instead of its compliance with standard practice.


On Tuesday, October 28, 2014 10:33 AM, Mitchell Williams <flyrotary@lancaironline.net> wrote:



On Mon, Oct 27, 2014 at 6:19 PM, Stephen Izett <flyrotary@lancaironline.net> wrote:
I stand corrected. I believe Charlie is correct.
Steve Izett


On 28 Oct 2014, at 6:47 am, Charlie England <flyrotary@lancaironline.net> wrote:

On 10/27/2014 4:55 PM, Ernest Christley wrote:
This is the type that I'm referring to:



On Monday, October 27, 2014 5:50 PM, Ernest Christley <flyrotary@lancaironline.net> wrote:


Is anyone familiar with electric fuel selector valves as used in automotive applications.  I'm trying to figure out how they operate.  Do they select one line when power is applied to a solenoid type plunger, and then the other line is selected when power isn't applied?  Or does a pulse of power switch them back and forth?  If they maintain the currently selected tank when power is absent, it seems to me that this could remove fuel lines and a leak prone selector valve from a lot of cockpits.  Furthermore, the 6 port models look like they could be plumbed easily to handle return lines.



The ones I've seen actually use a motor to move the valve (think screw jack), so they will remain in last position. Reading your linked item indicates that it works the same way.

'Traditional' engine guys have avoided them in the past because they're plastic and they require power (and they are an automotive product, so they can't be reliable ;-)  ). They are probably worth considering, but I'm seriously looking at switching to in-tank turbine pumps with automotive style PWM control; no return line needed. Then tank selection would be with a switch on the panel instead of a valve. Downside is that for total redundancy, I'd need 2 pumps in each tank. They are dirt cheap (<$20 each), but controllers are around $75 ea and switching gets pretty elaborate if there are more than 2 tanks.

Charlie




--
Mitchell Williams OKPE, ATP/CFI/A&P/IA   www.chickashawings.com
of shadow and ash http://www.amazon.com/dp/B009KZGVQS



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