X-Virus-Scanned: clean according to Sophos on Logan.com From: "steve Izett" Received: from mail-pf0-f169.google.com ([209.85.192.169] verified) by logan.com (CommuniGate Pro SMTP 6.2c1) with ESMTPS id 9606736 for flyrotary@lancaironline.net; Fri, 24 Mar 2017 19:36:56 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.192.169; envelope-from=steveize@gmail.com Received: by mail-pf0-f169.google.com with SMTP id o190so1946170pfo.0 for ; Fri, 24 Mar 2017 16:36:57 -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=ISjFyXyOJDjQYMpVLvrO+Oe3RyijgE6uNYBAPc5epgk=; b=U5yvUtqf8gU8ZovxUT8X6AJxTBztAN8CbD9oIVV4sG5BE1t3F12+93ffilZDl7Rqcp rzSEViXByeC6kY+/0/LpmamGKHJC7JjSIkyi9ftj4OVols4LXtdq8/NL9VG4OXKJ34Th lWRmCbo/i5pRPsYlOw4xlf9GWKTjF+fVMQdcRXbqm/ShRwSI8P+j3lwb8c6y5ujnZimJ I0yNHQC0dbwqz+tD03WPVuumuV0XDG+vcraWg/tqbLlqjohIjb/tdQwRM4Hq/48qDG+U aqH13KbRc30YYl6lgVcgnSpd8VIqF4GF60/2Ecyx2vCjNVNVK1a6C7SzhuFmWmYP/S2i pYTg== 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=ISjFyXyOJDjQYMpVLvrO+Oe3RyijgE6uNYBAPc5epgk=; b=FfGB6PV859XWUcYj+J3g7Y3x1PYP5phZRfBitiXOI38F9rYPMt5759XD5fc6hW1u7U FcRBQ7Z31cIixOS/3g35waPj+lk+zpICWfdvVPA+s3yzRZ3Rngby4/rJYyD5Pqf9ILhV Glc6pGh35qTC8f3/MFwb0Q09XkRIuU1L4lNdZuc5sLX97WkWtPMVbu7JCielVpMTP20u Hp5sLGoIYlRbMmTo+sK1EAThYgr3FzMW9shFJymCaxdty4XXYYU4pyUCtOzrRuMae82/ d38O66cXp3SHNLP9oS80zMy0Y8Zeehu5LV5QXlClg/EMS8Q65OQ3szsYTe/KBbkS26v7 pn7Q== X-Gm-Message-State: AFeK/H2Tj5wtbN0Wrk6dyMOQskTeqBBiB1GjS0KbntqZvqEqlRRE97On1dvDD8hP9KZhOA== X-Received: by 10.99.5.133 with SMTP id 127mr11802529pgf.8.1490398599351; Fri, 24 Mar 2017 16:36:39 -0700 (PDT) Return-Path: Received: from [10.1.1.6] ([124.169.71.123]) by smtp.gmail.com with ESMTPSA id 19sm6655691pfo.50.2017.03.24.16.36.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 24 Mar 2017 16:36:38 -0700 (PDT) Content-Type: multipart/alternative; boundary="Apple-Mail=_BAF214E2-F65E-451C-B664-47668B1F1725" Mime-Version: 1.0 (Mac OS X Mail 10.2 \(3259\)) Subject: Re: [FlyRotary] Re: Fuel Pump current and pressures Date: Sat, 25 Mar 2017 07:36:34 +0800 References: To: Rotary motors in aircraft In-Reply-To: Message-Id: X-Mailer: Apple Mail (2.3259) --Apple-Mail=_BAF214E2-F65E-451C-B664-47668B1F1725 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Hy Bobby. The would be a good test and fault finding technique. I=E2=80=99ll ponder how I can pull it off! Steve > On 25 Mar 2017, at 2:27 am, Bobby J. Hughes = wrote: >=20 > A good test would be to plumb around the regulator and check the = current. > =20 > Bobby > =20 > From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net = ]=20 > Sent: Friday, March 24, 2017 2:24 PM > To: Rotary motors in aircraft > Subject: [FlyRotary] Re: Fuel Pump current and pressures > =20 > Hey Steve,=20 >=20 > Just re-read your post with the measurements, & I'm not sure which had = higher current draw. It was the bottom pump, right? >=20 > Thanks, >=20 > Charlie >=20 > On 3/24/2017 8:06 AM, Stephen Izett wrote: > Good idea Charlie. =20 > That would clear it up as far as the manifold flow characteristics.=20 > Just a pain in the but to get to. > Thanks > Steve > =20 > =20 > =20 > 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=20 > 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 > =20 > =20 --Apple-Mail=_BAF214E2-F65E-451C-B664-47668B1F1725 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8 Hy Bobby.
The would be a good test and fault = finding technique.
I=E2=80=99ll ponder how I can = pull it off!
Steve
On 25 Mar 2017, at 2:27 am, = Bobby J. Hughes <flyrotary@lancaironline.net> wrote:

A good test would be to = plumb around the regulator and check the current.
 
Bobby
 
From: Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] 
Sent: Friday, March 24, 2017 2:24 = PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: Fuel Pump = current and pressures
 
Hey Steve, 

Just re-read your post with the measurements, & I'm not = sure which had higher current draw. It was the bottom pump, right?

Thanks,

Charlie

On 3/24/2017 8:06 AM, Stephen Izett wrote:
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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