X-Virus-Scanned: clean according to Sophos on Logan.com From: "Stephen Izett" Received: from mail-pg0-f45.google.com ([74.125.83.45] verified) by logan.com (CommuniGate Pro SMTP 6.2c1) with ESMTPS id 9604258 for flyrotary@lancaironline.net; Fri, 24 Mar 2017 09:06:56 -0400 Received-SPF: pass receiver=logan.com; client-ip=74.125.83.45; envelope-from=steveize@gmail.com Received: by mail-pg0-f45.google.com with SMTP id g2so863081pge.3 for ; Fri, 24 Mar 2017 06:06:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:mime-version:subject:date:references:to:in-reply-to:message-id; bh=zRx9a+BbVvtLonJV9s7So1uY+67142lbcGZZosy0/Q0=; b=jOhv6CqHlm57cEFIZpPgxLIa4Mpyff9VrgYrdmyYaJhFtj2gtqxjXjx/JVxqELiY1y aDvqqs0hwlBIYOcL9qFqtikP1oyR8Dvv1S+lgBiF4XETzyCosJNgOFy36BIzad4J+LvN tkeLCpTdHVwHdhSIJBAJBq2taMkwX6/c5QvpYMmnC8aY5bMtI2+XSNzLZrUkusj4OZBK jxQTtbmhUmpohTU5NbemtPRTgHoMkezv1hXJ9cUraFuj6dL7IVFKxeCmuqtz0R5b2Nt2 XNGNaorB1TALr4roDFEJP/rkjQ3zqBpmhzvoLB2ELCPRHT2A9ywpSCyl3HZMmtorx3kN VXqQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:mime-version:subject:date:references:to :in-reply-to:message-id; bh=zRx9a+BbVvtLonJV9s7So1uY+67142lbcGZZosy0/Q0=; b=H9Nq74tnSHCmvrdivm7cgH5+pNgPoi8u4yL/hmiLTcRNewHg/eINjTQntPEueERMie pGK2AcXvi4qrV0RGurHTHPZydaqN+U2opCSX5R3drwHYpDSnOQLfJ5vPaSKMdMw7n7Eg 5aT7zBwD/TDOpKOcEaJO/2JOTWo+hJ5lFH46BWl97VzGZWKAp1G+/fzCw4KC1Phu8DuP jsiG4cfj17Ciu5Ip4cYrEOmknVXw8IlYdsZwdpSGxGT9FLs+PJIhffB7uSFUtyd/8UHs vv4w1vi7L6rVCUisvcyt8WVM29NvQjrrw8fn3ZnBM6zgEBPhNUzAfijm8AkzkJn6fKgw PUWg== X-Gm-Message-State: AFeK/H14vtB2Tild0xlf05vg3dNO4hkXlBJSz3yQwtJG2Ltp8KBrjruI20rkw71SU6l+Jg== X-Received: by 10.98.214.4 with SMTP id r4mr8949230pfg.185.1490360797727; Fri, 24 Mar 2017 06:06:37 -0700 (PDT) Return-Path: Received: from [10.1.1.6] ([124.169.71.123]) by smtp.gmail.com with ESMTPSA id g27sm4791870pfk.95.2017.03.24.06.06.35 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 24 Mar 2017 06:06:36 -0700 (PDT) X-Google-Original-From: Stephen Izett Content-Type: multipart/alternative; boundary="Apple-Mail=_B404A434-A341-460F-B887-CEF1C89E3E5A" Mime-Version: 1.0 (Mac OS X Mail 10.2 \(3259\)) Subject: Re: [FlyRotary] Re: Fuel Pump current and pressures Date: Fri, 24 Mar 2017 21:06:32 +0800 References: To: Rotary motors in aircraft In-Reply-To: Message-Id: X-Mailer: Apple Mail (2.3259) --Apple-Mail=_B404A434-A341-460F-B887-CEF1C89E3E5A Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Good idea Charlie.=20 That would clear it up as far as the manifold flow characteristics. Just a pain in the but to get to. Thanks Steve > On 24 Mar 2017, at 8:56 pm, Charlie England = wrote: >=20 > Have you tried swapping the position of the pumps & making the same = measurements? It's hard to imagine it making that much difference, but = the bottom pump does have a tight right turn and then a sharp edged 'T' = turn to the left. I couldn't guess how much, but that would account for = at least some pressure increase.=20 >=20 > Charlie >=20 > On Fri, Mar 24, 2017 at 4:14 AM, steve Izett = > = wrote: > Hi Guys > Hi Peoples >=20 > Here is a photo of our parallel pumps plumbed with 3/8 aluminium lines = feed from a 28 gallon header tank above to the right. > Fuel then passes through the firewall and race filter before feeding = the rail and returning via the pressure regulator (4cyl toyota reg)=20 > back through the firewall to the header tank, again in 3/8. >=20 > I did further measurements today.=20 >=20 > 1. Bottom Pump only ~8A and 48psi - Turning both pumps on this pump = draws 9.9A and produces a rail pressure of 65psi > 2. Bottom Pump only ~9.9A and 44psi - Turning both pumps on this pump = draws 14.8A and produces the same rail pressure of 65psi >=20 > So bottom pump goes from 8.0 -> 9.9A (1.9A increase) under higher head = pressure > Top pump goes from 9.9A -> 14.8A (5.1A increase) under same head!! >=20 > Clearly Pressure Reg bypass capacity is inadequate for both pumps, = perhaps with even one pump running.=20 > (I don=E2=80=99t have data of fuel pressure under load to see if it = drops as power is applied) > I think I modelled the pump layout/manifold after seeing someone = else=E2=80=99s and not sure if it causes any problems? > The pumps came from eBay stating that they were genuine Walbro and now = I=E2=80=99m wondering. >=20 > Cheers >=20 > Steve Izett > Glasair Super II RG Renesis 4 port RD1C EC3 EM3=20 >=20 >=20 >=20 >=20 >=20 > >=20 --Apple-Mail=_B404A434-A341-460F-B887-CEF1C89E3E5A Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8 Good idea Charlie. 
That would clear it = up as far as the manifold flow characteristics.
Just a = pain in the but to get to.
Thanks
Steve



On = 24 Mar 2017, at 8:56 pm, Charlie England <flyrotary@lancaironline.net> wrote:

Have you tried swapping the position of the pumps & = making the same measurements? It's hard to imagine it making that much = difference, but the bottom pump does have a tight right turn and then a = sharp edged 'T' turn to the left. I couldn't guess how much, but that = would account for at least some pressure increase. 

Charlie

On Fri, = Mar 24, 2017 at 4:14 AM, steve Izett <flyrotary@lancaironline.net> wrote:
Hi Guys
Hi = Peoples

Here = is a photo of our parallel pumps plumbed with 3/8 aluminium lines feed = from a 28 gallon header tank above to the right.
Fuel= then passes through the firewall and race filter before feeding the = rail and returning via the pressure regulator (4cyl toyota = reg) 
back through the firewall to the header = tank, again in 3/8.

I did further measurements today. 

1. Bottom Pump = only ~8A and 48psi - Turning both pumps on this pump draws 9.9A and = produces a rail pressure of 65psi
2. Bottom Pump = only ~9.9A and 44psi - Turning both pumps on this pump draws 14.8A = and produces the same rail pressure of 65psi

So bottom pump goes from 8.0 -> 9.9A = (1.9A increase) under higher head pressure
Top pump = goes from 9.9A -> 14.8A (5.1A increase) under same head!!

Clearly Pressure Reg = bypass capacity is inadequate for both pumps, perhaps with even one pump = running. 
(I don=E2=80=99t have data of fuel = pressure under load to see if it drops as power is applied)
I think I modelled the pump layout/manifold after seeing = someone else=E2=80=99s and not sure if it causes any problems?
The pumps came from eBay stating that they were genuine = Walbro and now I=E2=80=99m wondering.

Cheers

Steve Izett
Glasair = Super II RG Renesis 4 port RD1C EC3 EM3 





<Fuel Pres = Pumps.JPG>


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