X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.103] (HELO ms-smtp-04-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 921620 for flyrotary@lancaironline.net; Sun, 01 May 2005 19:01:44 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-189-178.carolina.res.rr.com [24.74.189.178]) by ms-smtp-04-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j41N0uL5011577 for ; Sun, 1 May 2005 19:00:57 -0400 (EDT) Message-ID: <003401c54ea1$a24be070$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] fuel pumps Date: Sun, 1 May 2005 19:00:56 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0031_01C54E80.1B0351F0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0031_01C54E80.1B0351F0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Paul, I have two MSD pumps as well. At least one should run continuously to = keep your fuel line at the proper pressure for injection. They will = actually produce close to 80 psi with no flow. So a pressure regulator = is needed. I run both on take-off and landing - should one fail there = might not be time to react if only one was on. In the automobile (I just replace the in-tank fuel pump in my van = several months ago), the pump does turn on momentarily when you turn on = the key. This is simply to pressurize the line AND to provide the = initial fuel for starting. If the engine does not start the pump stays = off, if the engine starts, the pump turns back on - but, you can't hear = it over the engine. My HALTECH unit had a similar set up. It simply opened or close a pump = relay depending on whether it sense engine rpm. If the engine rpm was = zero the relay would not close thereby preventing you from pumping fuel = into the engine and out the tail pipe if the engine was not running. I = presume your MicroTech system has something similar. IF it does, I would wire one pump to the relay - use it for starting - = and the other pump would have a power toggle switch that I controlled - = my personal opinion of course. Ed A ----- Original Message -----=20 From: sqpilot@bellsouth.net=20 To: Rotary motors in aircraft=20 Sent: Monday, May 02, 2005 10:47 AM Subject: [FlyRotary] fuel pumps Hi all....I need to ask a question regarding the two EFI fuel pumps. = (I have two MSD pumps, I think they are something like 65 psi each). = Should these pumps run continuously? I know that on my automobile, when = you first turn the key (ignition), you can hear the fuel pump run for a = few seconds to pressurize the system, then it sounds like it shuts off. = On our aircraft, should they also do this or should they run = continuously, since the unused fuel is returned to the sump tank after = the fuel pressure regulator? I know that my MicroTech system has the = wire that supplies power to the fuel pumps going to a relay first, then = the power leaves the fuel pump relay and goes to the fuel pumps.=20 I know that most of you have Tracy's ECU system, but if I recall = correctly, I think that Ed Anderson had used an automotive ECU (another = brand) prior to changing to Tracy's ECU. Just wondering how that system = worked, regarding the fuel pumps.....constantly running or on demand. Thanks in advance for any and all info you guys might have = regarding how the EFI pumps are supposed to work. Paul Conner ------=_NextPart_000_0031_01C54E80.1B0351F0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Paul,
 
I have two MSD pumps as well.  At = least one=20 should run continuously to keep your fuel line at the proper pressure = for=20 injection.  They will actually produce close to 80 psi with no = flow. =20 So a pressure regulator is needed.  I run both on take-off and = landing -=20 should one fail there might not be time to react if only one was=20 on.
 
In the automobile (I just replace the = in-tank fuel=20 pump in my van several months ago), the pump does turn on momentarily = when you=20 turn on the key.  This is simply to pressurize the line AND to = provide the=20 initial fuel for starting.  If the engine does not start the pump = stays=20 off, if the engine starts, the pump turns back on - but, you can't hear = it over=20 the engine.
 
My HALTECH unit had a similar set = up.  It=20 simply opened or close a pump relay depending on whether it sense engine = rpm.  If the engine rpm was zero the relay would not close thereby=20 preventing you from pumping fuel into the engine and out the tail pipe = if the=20 engine was not running.  I presume your MicroTech system has = something=20 similar.
 
IF it does, I would wire one pump to = the relay -=20 use it for starting - and the other pump would have a power toggle = switch=20 that I controlled - my personal opinion of course.
 
Ed A
----- Original Message -----
From:=20 sqpilot@bellsouth.net
Sent: Monday, May 02, 2005 = 10:47 AM
Subject: [FlyRotary] fuel = pumps

Hi all....I need to ask a question = regarding the=20 two EFI fuel pumps. (I have two MSD pumps, I think they are something = like 65=20 psi each).  Should these pumps run continuously?  I know = that on my=20 automobile, when you first turn the key (ignition), you can hear the = fuel pump=20 run for a few seconds to pressurize the system, then it sounds like it = shuts=20 off. On our aircraft, should they also do this or should they run=20 continuously, since the unused fuel is returned to the sump tank after = the=20 fuel pressure regulator?  I know that my MicroTech system has the = wire=20 that supplies power to the fuel pumps going to a relay first, then the = power=20 leaves the fuel pump relay and goes to the fuel pumps.
     I know that = most of you=20 have Tracy's ECU system, but if I recall correctly, I think that Ed = Anderson=20 had used an automotive ECU (another brand) prior to changing to = Tracy's=20 ECU.  Just wondering how that system worked, regarding the fuel=20 pumps.....constantly running or on demand.
     Thanks in = advance for=20 any and all info you guys might have regarding how the EFI pumps are = supposed=20 to work.  Paul Conner
 
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