X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 09 May 2008 13:48:24 -0400 Message-ID: X-Original-Return-Path: Received: from bay0-omc2-s20.bay0.hotmail.com ([65.54.246.156] verified) by logan.com (CommuniGate Pro SMTP 5.2.3) with ESMTP id 2914059 for lml@lancaironline.net; Thu, 08 May 2008 15:51:38 -0400 Received-SPF: pass receiver=logan.com; client-ip=65.54.246.156; envelope-from=ian.crowe@sympatico.ca Received: from BAYC1-PASMTP04 ([65.54.191.164]) by bay0-omc2-s20.bay0.hotmail.com with Microsoft SMTPSVC(6.0.3790.3959); Thu, 8 May 2008 12:50:55 -0700 X-Originating-IP: [69.159.74.130] X-Originating-Email: [ian.crowe@sympatico.ca] X-Original-Message-ID: X-Original-Return-Path: ian.crowe@sympatico.ca Received: from IanCrowePC ([69.159.74.130]) by BAYC1-PASMTP04.bayc1.hotmail.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.2668); Thu, 8 May 2008 12:50:55 -0700 From: "Ian Crowe" X-Original-To: "Lancair Mailing List" Subject: Lancair 320 low fuel pressure X-Original-Date: Thu, 8 May 2008 15:50:44 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0238_01C8B123.463DB500" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6000.16480 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6000.16545 X-OriginalArrivalTime: 08 May 2008 19:50:55.0775 (UTC) FILETIME=[D44CBAF0:01C8B144] This is a multi-part message in MIME format. ------=_NextPart_000_0238_01C8B123.463DB500 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable You have to look where your fuel pressure is generated. Presumably you = have an engine driven pump feed the carburettor. I also assume from = your E mail you have an electric boost pump. Do you have a transfer = pump for each tank feeding the ready use tank (Header)? If you have the conventional Lancair fuel set up (with header tank) then = as long as you can pump fuel into the header tank you have more than = enough air going into the the main tanks through the vents. They are = not there to blow fuel into the the system but to vent the tank and = allow air to flow in as the fuel flows out. Even standing still with no = speed induced airflow going into the vent will still allow you to = transfer fuel from the tanks to the header. So as long as the vents are = clear all the way into the tank you are OK. Before you do anything check your pressure gauge. If your gauge is = electric put a "T" in the line to the sender and connect a mechanical = gauge. Compare the two gauges and trust the mechanical gauge. If all = is OK proceed as below So assuming you fill the header tank you now have a positive pressure at = the carburettor due to the height of the tank above the carb. Not much = to be sure but if the tank is 24" above the carb you have 1 lb/sq inch = roughly and yes this will vary with density altitude. =20 My next assumption is that your electric boost pump is next in line = after the header tank. I do not know what type of pump you have but = there will be some type of pressure regulator to set the pressure. This = may have picked up some dirt in the building process and the spring = loaded relief valve may be held open slightly which will stop the = pressure regulating. Put a pressure gauge on the pump output and = determine the pump pressure. The engine driven pump needs to be checked = next and that needs a bench check. You already know it does not pump. When you have done all the above and if you have found nothing then you = need an AME!!!!! I know the minimum pressure is 0.5 psi but for me that = is far too close to zero! I would have to find out what is going on = before I flew again. Something is amiss. Good luck! Ian Crowe Ian B. Crowe LNC2 C-FKRO (Fuel Injected, no header tank) ------=_NextPart_000_0238_01C8B123.463DB500 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
You have to look where your fuel = pressure is=20 generated.  Presumably you have an engine driven pump feed the=20 carburettor.  I also assume from your E mail you have an electric = boost=20 pump.  Do you have a transfer pump for each tank feeding the ready = use tank=20 (Header)?
 
If you have the conventional Lancair = fuel set up=20 (with header tank) then as long as you can pump fuel into the header = tank you=20 have more than enough air going into the the main tanks through the = vents. =20 They are not there to blow fuel into the the system but to vent the tank = and=20 allow air to flow in as the fuel flows out.  Even standing still = with no=20 speed induced airflow going into the vent will still allow you to = transfer fuel=20 from the tanks to the header.  So as long as the vents are clear = all the=20 way into the tank you are OK.
 
Before you do anything check = your pressure=20 gauge.  If your gauge is electric put a "T" in the line to the = sender and=20 connect a mechanical gauge.  Compare the two gauges and trust the=20 mechanical gauge.  If all is OK proceed as = below
 
So assuming you fill the header tank = you now have a=20 positive pressure at the carburettor due to the height of the tank above = the=20 carb.  Not much to be sure but if the tank is 24" above the carb = you have 1=20 lb/sq inch roughly and yes this will vary with density altitude. =20
 
My next assumption is that your = electric boost pump=20 is next in line after the header tank.  I do not know what type of = pump you=20 have but there will be some type of pressure regulator to set the=20 pressure.  This may have picked up some dirt in the building = process and=20 the spring loaded relief valve may be held open slightly which will stop = the=20 pressure regulating.  Put a pressure gauge on the pump output and = determine=20 the pump pressure.  The engine driven pump needs to be checked next = and=20 that needs a bench check.  You already know it does not = pump.
 
When you have done all the above and if = you have=20 found nothing then you need an AME!!!!!  I know the minimum = pressure=20 is 0.5 psi but for me that is far too close to zero!  I would have = to find=20 out what is going on before I flew again.  Something is = amiss.
 
Good luck!
 
Ian Crowe
Ian B. Crowe
 LNC2  C-FKRO = (Fuel=20 Injected, no header tank)
 
 
 
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