X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 27 Mar 2012 23:32:05 -0400 Message-ID: X-Original-Return-Path: Received: from oproxy1-pub.bluehost.com ([66.147.249.253] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with SMTP id 5458988 for lml@lancaironline.net; Tue, 27 Mar 2012 20:05:06 -0400 Received-SPF: pass receiver=logan.com; client-ip=66.147.249.253; envelope-from=danny@n107sd.com Received: (qmail 16515 invoked by uid 0); 28 Mar 2012 00:04:31 -0000 Received: from unknown (HELO host295.hostmonster.com) (66.147.240.95) by oproxy1.bluehost.com with SMTP; 28 Mar 2012 00:04:31 -0000 Received: from pool-71-114-20-44.washdc.dsl-w.verizon.net ([71.114.20.44] helo=DannyLaptop) by host295.hostmonster.com with esmtpa (Exim 4.76) (envelope-from ) id 1SCgNJ-0005xP-L3 for lml@lancaironline.net; Tue, 27 Mar 2012 18:04:31 -0600 From: "Danny" X-Original-To: "'Lancair Mailing List'" Subject: LNC2 gear diagnosis X-Original-Date: Tue, 27 Mar 2012 20:04:25 -0400 X-Original-Message-ID: <00bb01cd0c76$58018020$08048060$@com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00BC_01CD0C54.D0EFE020" X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: Ac0MdlYb35mhp9apTm+ZfOYARYwonQ== Content-language: en-us X-Identified-User: {3234:host295.hostmonster.com:wunderwe:n107sd.com} {sentby:smtp auth 71.114.20.44 authed with danny@n107sd.com} This is a multi-part message in MIME format. ------=_NextPart_000_00BC_01CD0C54.D0EFE020 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable If any of you have a suggestion, I=92d appreciate your input. =20 On my last flight home, with no early signs of failure, my gear pump was tripping on about every 2 seconds to maintain pressure. I figured I had = a leaky actuator and would have to rebuild it to resolve this; no big = deal. I found one leaking and figured where there is one, there may be more. = So, I=92m rebuilding all of them. But, before doing so, I put a gauge on = the high pressure side of the pump to see if I had internal leaks there too. = What I found was that my pump will only pressurize to about 950 psi (should be ~1200 psi) and then it bleeds down slowly. I tried to adjust the = pressure switch but it made very little difference. To verify the bleeding, I isolated all actuators out of the system except the nose wheel. I put = the gauge on the high pressure side of the NW actuator line, selected gear = up to pressurize the system, and then quickly crawled under the plane to look = at the gauge. It was bleeding down so fast that by the time I got down = there to look at it (~2 sec.), it had already lost about 200 psi and then bled down the rest of the way in about 7 more seconds. So, and here=92s the question, do I have a faulty gear dump valve, a leaky pump, or both? =20 =20 Danny LNC2-360, ~550 hours N 38=B0 43' 25.7" W 77=B0 30' 38.6" =20 ------=_NextPart_000_00BC_01CD0C54.D0EFE020 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

If = any of you have a suggestion, I’d appreciate your = input.

 

On = my last flight home, with no early signs of failure, my gear pump was = tripping on about every 2 seconds to maintain pressure.=A0 I figured I had a leaky actuator = and would have to rebuild it to resolve this; no big deal.=A0 I found one leaking and figured = where there is one, there may be more.=A0 So, I’m rebuilding all of = them.=A0 But, before doing so, I = put a gauge on the high pressure side of the pump to see if I had = internal leaks there too.=A0 = What I found was that my pump will only pressurize to about 950 = psi (should be ~1200 psi) and then it bleeds down slowly.=A0 I tried to adjust the pressure = switch but it made very little difference.=A0 To verify the bleeding, I isolated = all actuators out of the system except the nose wheel.=A0 I put the gauge on the high = pressure side of the NW actuator line, selected gear up to pressurize = the system, and then quickly crawled under the plane to look at the = gauge.=A0 It was bleeding down = so fast that by the time I got down there to look at it (~2 sec.), it = had already lost about 200 psi and then bled down the rest of the way in = about 7 more seconds.=A0 So, and = here’s the question, do I have a faulty gear dump valve, a leaky = pump, or both?

 

 

Danny

LNC2-360, ~550 = hours

N 38=B0 43' = 25.7"

W 77=B0 30' = 38.6"

 

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