X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 16 Jul 2008 07:51:38 -0400 Message-ID: X-Original-Return-Path: Received: from mailrelay.embarq.synacor.com ([208.47.184.3] verified) by logan.com (CommuniGate Pro SMTP 5.2.5) with ESMTP id 3028152 for lml@lancaironline.net; Wed, 16 Jul 2008 06:56:17 -0400 Received-SPF: pass receiver=logan.com; client-ip=208.47.184.3; envelope-from=liegner@embarqmail.com X-Original-Return-Path: X_CMAE_Category: 0,0 Undefined,Undefined X-CNFS-Analysis: v=1.0 c=1 a=q8yYKvpd4-AA:10 a=Ia-xEzejAAAA:8 a=lT6h65w8AAAA:8 a=m2giflinAAAA:8 a=m7_R-6C21phnhGtDsCUA:9 a=PuxqMLMu-bOd9ZMaNcUA:7 a=tyNsl_xbd5veyFk-oAzRX93H0dgA:4 a=-fq1EbaV3JEA:10 a=eLi5349b8ycA:10 a=ZDokJ3CvDCcA:10 a=PM3h3NMDdTMA:10 a=CWfAmLVWKswA:10 a=OV4U5KLcsFVhlIGA5KwA:9 a=LTbk_XV_G8x9q3stw_YA:7 a=h_B3j89vv0XAiGQ0NfuBRypB5vwA:4 a=AfD3MYMu9mQA:10 X-CM-Score: 0 X-Scanned-by: Cloudmark Authority Engine Authentication-Results: smtp07.embarq.synacor.com smtp.user=liegner@embarqmail.com; auth=pass (LOGIN) Received: from [76.6.59.235] ([76.6.59.235:27237] helo=[172.16.1.2]) by mailrelay.embarq.synacor.com (envelope-from ) (ecelerity 2.2.1.28 r(22594)) with ESMTPA id CC/67-10935-9A3DD784; Wed, 16 Jul 2008 06:55:37 -0400 Mime-Version: 1.0 X-Sender: liegner@embarqmail.com@pop.embarqmail.com X-Original-Message-Id: In-Reply-To: References: X-Original-Date: Wed, 16 Jul 2008 06:53:11 -0400 X-Original-To: "Lancair Mailing List" From: "Jeffrey Liegner, MD" Subject: Re: 4P Door seal pump operation at altitude X-Original-Cc: "John C. Bohn" Content-Type: multipart/alternative; boundary="============_-995916724==_ma============" --============_-995916724==_ma============ Content-Type: text/plain; charset="us-ascii" ; format="flowed" I've had this same problem for the last year. Problems with maintaining cabin pressurization. http://lancaironline.net:81/Lists/lml/Message/46348.html http://lancaironline.net:81/Lists/lml/Message/43714.html My serial number is 464 (c2000), so the pump from a batch is 8 years old. My problem has been them same, up to altitude >20K, great PSI differential (5psi), but after two hours-plus, the door cabin pressure starts leaking out slowly, PSI differential decreases, cabin climbs above 10K and higher. If I wait, I can see a sliver daylight between seal and frame. I might even hear a slight wistle of leaking air (in flight, hard to tell). I'd stuff cellophane into the gap during flight...carried a role of kitchen plastic...to buy me more altitude flight time. The door seal works well (5psi held for >1hr) on the ground, holds its inflation without leak for an hour or two, the pump works on the ground, the light comes on the panel showing power delivered to the pump (but with engine on, who can tell if pump is running), the valve works. I was baffled why this was happening. I checked and serviced my Duke's valve...twice...no luck. I beefed up the door perimeter, bringing it closer to the seal....no help. I occluded the pneumatic door valve/switch outflow to block leakage. I then replaced the switch....no help. I checked volts across the pressure sensor/switch, and found my panel LED would come on at 9V (as the seal pressure came down and the sensor started to activate), but my pump would not come on until ~12V...maybe...nope, not the issue. I finally concluded with some inflight in line LEDs after the pump that the pump was not coming on in the air despite >12V from the sensor/switch delivered properly (and the panel light ON). I then checked the pump with a 12V battery, and found that it gets stuck sometimes, not running despite having power applied. I recently ordered a new pump and placed it in parallel with the old pump during some ground tests. Sure enough, the new one came on and stayed on at 9V when the old one did not, when the sensor/switch was calling for pump, even up into the 12V range. Today I replace the door pump on the mount. Purchased from Lancair Parts. I hope this finally solves my problem. I'm confident it will. Jeff L LIVP >the replacement pumps are 265.00. > >Thank You > >Michelle Gagermeier >Parts sales >Kit Components INC. >phone 541-923-2244 >fax 541-548-7332 >www.aerocraftparts.com >www.lancair.com >michelleg@lancair.com > > >My door seal pump works fine on the ground i.e. it turns on and >shuts off at the proper pressure settings. At altitude on a long >trip over 3 or 4 hours the door seal light comes on but the pump >doesn't run. I thought I fixed the problem as I found the >connectors in the overhead somewhat loose so I secured them but now >I'm finding some arcing on the center (assuming power) post and if I >use a small screw driver and try to complete the connection the pump >barely wants to start (hard to complete circuit) it just arcs. I'm >getting good alignment between the door and airframe posts and what >I assume to be good spring pressure so I'm speculating the >temperature of the wires/posts (at altitude is very cold) isn't >providing good conductivity to complete the circuit. Has anyone >else seen this or can assist in troubleshooting? > >John C. Bohn >Lancair 4P N28487 >Direct (Cell)- 503-887-2933 --============_-995916724==_ma============ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Re: 4P Door seal pump operation at altitude
I've had this same problem for the last year.  Problems with maintaining cabin pressurization.
http://lancaironline.net:81/Lists/lml/Message/46348.html
http://lancaironline.net:81/Lists/lml/Message/43714.html

My serial number is 464 (c2000), so the pump from a batch is 8 years old.  My problem has been them same, up to altitude >20K, great PSI differential (5psi), but after two hours-plus, the door cabin pressure starts leaking out slowly, PSI differential decreases, cabin climbs above 10K and higher.  If I wait, I can see a sliver daylight between seal and frame.  I might even hear a slight wistle of leaking air (in flight, hard to tell).  I'd stuff cellophane into the gap during flight...carried a role of kitchen plastic...to buy me more altitude flight time.

The door seal works well (5psi held for >1hr) on the ground, holds its inflation without leak for an hour or two, the pump works on the ground, the light comes on the panel showing power delivered to the pump (but with engine on, who can tell if pump is running), the valve works.  I was baffled why this was happening.

I checked and serviced my Duke's valve...twice...no luck.
I beefed up the door perimeter, bringing it closer to the seal....no help.
I occluded the pneumatic door valve/switch outflow to block leakage.  I then replaced the switch....no help.
I checked volts across the pressure sensor/switch, and found my panel LED would come on at 9V (as the seal pressure came down and the sensor started to activate), but my pump would not come on until ~12V...maybe...nope, not the issue.

I finally concluded with some inflight in line LEDs after the pump that the pump was not coming on in the air despite >12V from the sensor/switch delivered properly (and the panel light ON).  I then checked the pump with a 12V battery, and found that it gets stuck sometimes, not running despite having power applied.

I recently ordered a new pump and placed it in parallel with the old pump during some ground tests.  Sure enough, the new one came on and stayed on at 9V when the old one did not, when the sensor/switch was calling for pump, even up into the 12V range.

Today I replace the door pump on the mount.  Purchased from Lancair Parts.  I hope this finally solves my problem.  I'm confident it will.

Jeff L
LIVP


the replacement pumps are 265.00.

Thank You
Michelle Gagermeier
Parts sales
Kit Components INC.
phone 541-923-2244
fax 541-548-7332
www.aerocraftparts.com
www.lancair.com
michelleg@lancair.com 




My door seal pump works fine on the ground i.e. it turns on and shuts off at the proper pressure settings.  At altitude on a long trip over 3 or 4 hours the door seal light comes on but the pump doesnıt run.  I thought I fixed the problem as I found the connectors in the overhead somewhat loose so I secured them but now Iım finding some arcing on the center (assuming power) post and if I use a small screw driver and try to complete the connection the pump barely wants to start (hard to complete circuit) it just arcs.  Iım getting good alignment between the door and airframe posts and what I assume to be good spring pressure so Iım speculating the temperature of the wires/posts (at altitude is very cold) isnıt providing good conductivity to complete the circuit.  Has anyone else seen this or can assist in troubleshooting?
 
John C. Bohn
Lancair 4P N28487
Direct (Cell)- 503-887-2933

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