X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imf19aec.mail.bellsouth.net ([205.152.59.67] verified) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 933126 for flyrotary@lancaironline.net; Thu, 05 May 2005 00:20:05 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.67; envelope-from=sqpilot@bellsouth.net Received: from paul52u7f5qyav ([209.214.45.48]) by imf19aec.mail.bellsouth.net (InterMail vM.5.01.06.11 201-253-122-130-111-20040605) with SMTP id <20050505041916.MSME2470.imf19aec.mail.bellsouth.net@paul52u7f5qyav> for ; Thu, 5 May 2005 00:19:16 -0400 Message-ID: <017f01c55129$9727bcc0$302dd6d1@paul52u7f5qyav> From: "Paul" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: fuel pumps/forced landing Date: Wed, 4 May 2005 23:19:10 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_017C_01C550FF.AD8711C0" 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 This is a multi-part message in MIME format. ------=_NextPart_000_017C_01C550FF.AD8711C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi, Dave....the representative from MicroTech told me that the ECU shuts = off power to the fuel pump relay if the ECU detects no spark to the = plugs, derived from lack of electical current. Paul Conner ----- Original Message -----=20 From: David Staten=20 To: Rotary motors in aircraft=20 Sent: Monday, May 02, 2005 7:53 AM Subject: [FlyRotary] Re: fuel pumps/forced landing The"ignition" system is shutting off the pump once adequate head = pressure is obtained. Its not the engine starting that directly triggers = the pump. Its the engine using the fuel in the rail, lowering the = pressure below the triggering threshold on some pressure sensor = somewhere, causing a logic circuit to turn the pump back on. The = feedback loop in this situation is based on fuel pressure. =20 Dave William wrote: Paul, If your ignition system shuts off the pump with no spark, isn't the = following going to happen? Pump 1 on -- engine running, pump 1 fuse blows, engine shuts down very quickly, Pump 2 turned on, but no spark since engine has stopped, therefore = it shuts off right away. Sounds like if engine stops, you have to crank it to get it started = again Bill Schertz KIS Cruiser # 4045 ----- Original Message -----=20 From: sqpilot@bellsouth.net=20 To: Rotary motors in aircraft=20 Sent: Monday, May 02, 2005 1:42 PM Subject: [FlyRotary] Re: fuel pumps/forced landing Turned on the other pump, but the engine had already quit. (yes, = it happens very fast) =20 I now recall reading in the MicroTech manual that the fuel = pumps shut off if it detects no spark from the coils, so that it would = not continue pumping fuel into an engine that has no spark. This is = obviously why the pump only runs for a few seconds when I first turn on = the ignition switch, then quickly stops pumping. We put a voltmeter to = the inline fuse, and found that it had 12.9 volts as soon as the = ignition was turned on, but after a few seconds, the pump stopped and = there was no longer any voltage at the fuse.=20 I'm hoping we can find what caused the slight fuel obstruction = in front of the gascolator....if we can't find the cause, it would be = difficult to regain confidence in the fuel system. Too bad, because the = engine was running strong and smooth, and the temps were great!!! Paul = aka deadstick Conner >> Homepage: http://www.flyrotary.com/ >> Archive: = http://lancaironline.net/lists/flyrotary/List.html-----------------------= -------------------------------------------------------No virus found in = this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.11.1 - Release Date: 5/2/2005 ------=_NextPart_000_017C_01C550FF.AD8711C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi, Dave....the representative from = MicroTech told=20 me that the ECU shuts off power to the fuel pump relay if the ECU = detects no=20 spark to the plugs, derived from lack of electical current. Paul=20 Conner
 
----- Original Message -----
From:=20 David=20 Staten
Sent: Monday, May 02, 2005 7:53 = AM
Subject: [FlyRotary] Re: fuel=20 pumps/forced landing

The"ignition" system is shutting off the pump once = adequate=20 head pressure is obtained. Its not the engine starting that directly = triggers=20 the pump. Its the engine using the fuel in the rail, lowering the = pressure=20 below the triggering threshold on some pressure sensor somewhere, = causing a=20 logic circuit to turn the pump back on. The feedback loop in this = situation is=20 based on fuel pressure.
 
Dave

William wrote:
Paul,
If your ignition system shuts off = the pump with=20 no spark, isn't the following going to happen?
 
Pump 1 on -- engine = running,
pump 1 fuse blows, engine shuts = down very=20 quickly,
Pump 2 turned on, but no spark = since engine has=20 stopped, therefore it shuts off right away.
 
Sounds like if engine stops, you = have to crank=20 it to get it started again
Bill Schertz
KIS Cruiser # 4045
-----=20 Original Message ----- From:=20 sqpilot@bellsouth.net = To:=20 Rotary motors in = aircraft=20 Sent:=20 Monday, May 02, 2005 1:42 PM Subject:=20 [FlyRotary] Re: fuel pumps/forced landing
 Turned on the other pump, = but=20 the engine had already quit. (yes, it happens very=20 fast)  
 
      I = now recall=20 reading in the MicroTech manual that the fuel pumps shut off if it = detects=20 no spark from the coils, so that it would not continue pumping = fuel into=20 an engine that has no spark. This is obviously why the pump only = runs for=20 a few seconds when I first turn on the ignition switch, then = quickly stops=20 pumping. We put a voltmeter to the inline fuse, and found that it = had 12.9=20 volts as soon as the ignition was turned on, but after a few = seconds, the=20 pump stopped and there was no longer any voltage at the fuse.=20
    I'm hoping we = can find=20 what caused the slight fuel obstruction in front of the = gascolator....if=20 we can't find the cause, it would be difficult to regain = confidence in the=20 fuel system. Too bad, because the engine was running strong and = smooth,=20 and the temps were great!!!  Paul aka deadstick=20 Conner

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