X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 19 Sep 2013 07:43:43 -0400 Message-ID: X-Original-Return-Path: <2thman1@gmail.com> Received: from mail-pd0-f170.google.com ([209.85.192.170] verified) by logan.com (CommuniGate Pro SMTP 6.0.7) with ESMTPS id 6481248 for lml@lancaironline.net; Wed, 18 Sep 2013 23:31:23 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.192.170; envelope-from=2thman1@gmail.com Received: by mail-pd0-f170.google.com with SMTP id x10so7918066pdj.29 for ; Wed, 18 Sep 2013 20:30:47 -0700 (PDT) X-Received: by 10.68.254.132 with SMTP id ai4mr24843932pbd.51.1379561447102; Wed, 18 Sep 2013 20:30:47 -0700 (PDT) X-Original-Return-Path: <2thman1@gmail.com> Received: from [192.168.1.137] (c-208-53-115-208.customer.broadstripe.net. [208.53.115.208]) by mx.google.com with ESMTPSA id hx1sm6019681pbb.35.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 18 Sep 2013 20:30:46 -0700 (PDT) References: In-Reply-To: Mime-Version: 1.0 (1.0) Content-Type: multipart/alternative; boundary=Apple-Mail-055939DC-CABE-4E70-9E77-FB340732B5C2 X-Original-Message-Id: Content-Transfer-Encoding: 7bit X-Mailer: iPad Mail (10B329) From: John Barrett <2thman1@gmail.com> Subject: Re: [LML] IVP pressurization X-Original-Date: Wed, 18 Sep 2013 20:30:44 -0700 X-Original-To: Lancair Mailing List --Apple-Mail-055939DC-CABE-4E70-9E77-FB340732B5C2 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Many of you have supplied very useful tips in response to my questions. Sin= ce then I've found some substantial leaks that are probably the issue. I wo= nder if others have had leaks in the tunnel under the spar box that hydrauli= c and fuel lines go through? I have a significant one here and I fear I wil= l have to stop it in order to get adequate pressurization. Has anyone else d= ealt with this after the lines are all in and the a/c is flying? I think I c= an seal up the tunnel front and back but it will likely take a good bit of s= ome kind of goop to do it. =20 Thanks for any advice. John Barrett N31VP Sent from my iPad On Sep 6, 2013, at 12:40 PM, Jack Morgan wrote: > Hi John, >=20 > Attached is a pic of the wedge. I used controller rather than outflow valv= e throughout my first posting on this. Outflow valve is a better description= . You interpreted my suggestions correctly. >=20 > Here is a pic of the wedge. Length from the bend is 4". The slot is 7/8" w= ide and the short angle section is 1". The overall width is 4". The slot is 2= .5" deep. The piece is scrap from something on a IV..... sorry I have forgot= ten what but hopefully it is still lying around your shop. the other two bit= s are what I used to set the tension holding the outflow valve closed. >=20 > I noted a suggestion that you block off the outflow valve tub from the top= and fly the airplane. Keep in mind that the over pressure pop off valve wil= l also be disabled if you do this since if is normally in the tub. I would d= ouble check that you can't over pressurize the cabin and damage it before tr= ying that suggestion. I assume but don't actually know that the pop off valv= e protection is required if the outflow valve jams closed. >=20 > My mixing box came from Lancair with the pressure dump and temp mix levers= only partially tightened. One of my early discoveries was that the pressure= dump flapper worked intermittently until I tightened the lever securely. Yo= u have either a big leak, bad outflow valve, or leaky pressure input to the c= abin if you are only getting 1/2 PSI. I was able to get 3.5 PSI before I fou= nd my last significant leak. It was easily found with two shop vacs but not w= ith one. >=20 > Hope this helps. >=20 > Jack > >=20 > On Sep 5, 2013, at 6:01 AM, Lancair Mailing List wrote: >=20 >> From: John Barrett <2thman1@gmail.com> >> Subject: IVP pressurization >> Date: September 4, 2013 7:42:10 AM EDT >> To: lml@lancaironline.net >=20 --Apple-Mail-055939DC-CABE-4E70-9E77-FB340732B5C2 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Many of you have supplied very useful t= ips in response to my questions.  Since then I've found some substantia= l leaks that are probably the issue.  I wonder if others have had leaks= in the tunnel under the spar box that hydraulic and fuel lines go through? &= nbsp;I have a significant one here and I fear I will have to stop it in orde= r to get adequate pressurization. Has anyone else dealt with this after the l= ines are all in and the a/c is flying?  I think I can seal up the tunne= l front and back but it will likely take a good bit of some kind of goop to d= o it.  

Thanks for any advice.
John B= arrett
N31VP

Sent from my iPad

On Sep 6, 2013, at 12:40 PM, Jack Morgan <jmorgan1023@comcast.net> wrote:

Hi John,

Attached is a pic of the wed= ge. I used controller rather than outflow valve throughout my first posting o= n this. Outflow valve is a better description. You interpreted my suggestion= s correctly.

Here is a pic  of the wedge. Leng= th from the bend is 4". The slot is 7/8" wide and the short angle section is= 1". The overall width is 4". The slot is 2.5" deep. The piece is scrap from= something on a IV..... sorry I have forgotten what but hopefully it is stil= l lying around your shop. the other two bits are what I used to set the tens= ion holding the outflow valve closed.

I noted a sug= gestion that you block off the outflow valve tub from the top and fly the ai= rplane. Keep in mind that the over pressure pop off valve will also be disab= led if you do this since if is normally in the tub. I would double check tha= t you can't over pressurize the cabin and damage it before trying that sugge= stion. I assume but don't actually know that the pop off valve protection is= required if the outflow valve jams closed.

My mixi= ng box came from Lancair with the pressure dump and temp mix levers only par= tially tightened. One of my early discoveries was that the pressure dump fla= pper worked intermittently until I tightened the lever securely. You have ei= ther a big leak, bad outflow valve, or leaky pressure input to the cabin if y= ou are only getting 1/2 PSI. I was able to get 3.5 PSI before I found my las= t significant leak. It was easily found with two shop vacs but not with one.=

Hope this helps.

Jack
<IV Pwedge.jpeg>

On Sep 5, 2013, at 6:0= 1 AM, Lancair Mailing List wrote:

From:=  John Barrett <= 2thman1@gmail.com>
Subjec= t: IVP pressurization
<= /span>
Date: September 4, 2013 7:42:10 AM EDT


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