X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 16 Jul 2008 11:12:03 -0400 Message-ID: X-Original-Return-Path: Received: from imo-m14.mx.aol.com ([64.12.138.204] verified) by logan.com (CommuniGate Pro SMTP 5.2.5) with ESMTP id 3028466 for lml@lancaironline.net; Wed, 16 Jul 2008 10:29:36 -0400 Received: from VTAILJEFF@aol.com by imo-m14.mx.aol.com (mail_out_v38_r9.3.) id q.c2a.2eb9391a (37568) for ; Wed, 16 Jul 2008 10:29:32 -0400 (EDT) Received: from smtprly-ma03.mx.aol.com (smtprly-ma03.mx.aol.com [64.12.207.142]) by cia-mb04.mx.aol.com (v121.5) with ESMTP id MAILCIAMB045-92c0487e05cbdf; Wed, 16 Jul 2008 10:29:31 -0400 Received: from MBLK-M06 (mblk-m06.mblk.aol.com [64.12.136.39]) by smtprly-ma03.mx.aol.com (v121_r2.10) with ESMTP id MAILSMTPRLYMA038-5c5a487e05bfb6; Wed, 16 Jul 2008 10:29:19 -0400 References: X-Original-To: lml@lancaironline.net Subject: Re: [LML] Re: 4P Door seal pump operation at altitude X-Original-Date: Wed, 16 Jul 2008 10:29:19 -0400 X-AOL-IP: 75.49.225.53 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: vtailjeff@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CAB56777DCD5A2_D44_918C_MBLK-M06.sysops.aol.com" X-Mailer: AOL Webmail 37668-STANDARD Received: from 75.49.225.53 by MBLK-M06.sysops.aol.com (64.12.136.39) with HTTP (WebMailUI); Wed, 16 Jul 2008 10:29:19 -0400 X-Original-Message-Id: <8CAB56777D5AEA0-D44-49CC@MBLK-M06.sysops.aol.com> X-Spam-Flag: NO ----------MB_8CAB56777DCD5A2_D44_918C_MBLK-M06.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Jeff L. Great analysis. Jeff -----Original Message----- From: Jeffrey Liegner, MD To: lml@lancaironline.net Sent: Wed, 16 Jul 2008 6:51 am Subject: [LML] Re: 4P Door seal pump operation at altitude I've had this same problem for the last year.=C2=A0 Problems with maintainin= g 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.= =C2=A0 My problem has been them same, up to altitude >20K, great PSI differe= ntial (5psi), but after two hours-plus, the door cabin pressure starts leaki= ng out slowly, PSI differential decreases, cabin climbs above 10K and higher= .=C2=A0 If I wait, I can see a sliver daylight between seal and frame.=C2= =A0 I might even hear a slight wistle of leaking air (in flight, hard to tel= l).=C2=A0 I'd stuff cellophane into the gap during flight...carried a role o= f kitchen plastic...to buy me more altitude flight time. The door seal works well (5psi held for >1hr) on the ground, holds its infla= tion without leak for an hour or two, the pump works on the ground, the ligh= t comes on the panel showing power delivered to the pump (but with engine on= , who can tell if pump is running), the valve works.=C2=A0 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.=C2=A0 I then replaced the switch....no help= . I checked volts across the pressure sensor/switch, and found my panel LED wo= uld come on at 9V (as the seal pressure came down and the sensor started to=20= activate), but my pump would not come on until ~12V...maybe...nope, not the=20= issue. I finally concluded with some inflight in line LEDs after the pump that the=20= pump was not coming on in the air despite >12V from the sensor/switch delive= red properly (and the panel light ON).=C2=A0 I then checked the pump with a=20= 12V battery, and found that it gets stuck sometimes, not running despite hav= ing power applied. I recently ordered a new pump and placed it in parallel with the old pump du= ring some ground tests.=C2=A0 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.=C2=A0 Purchased from Lancair Par= ts.=C2=A0 I hope this finally solves my problem.=C2=A0 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=C2=A0 My door seal pump works fine on the ground i.e. it turns on and shuts off at= the proper pressure settings.=C2=A0 At altitude on a long trip over 3 or 4=20= hours t he door seal light comes on but the pump doesn=C2=B9t run.=C2=A0 I thought I= fixed the problem as I found the connectors in the overhead somewhat loose=20= so I secured them but now I=C2=B9m finding some arcing on the center (assumi= ng power) post and if I use a small screw driver and try to complete the con= nection the pump barely wants to start (hard to complete circuit) it just ar= cs.=C2=A0 I=C2=B9m getting good alignment between the door and airframe post= s and what I assume to be good spring pressure so I=C2=B9m speculating the t= emperature of the wires/posts (at altitude is very cold) isn=C2=B9t providin= g good conductivity to complete the circuit.=C2=A0 Has anyone else seen this= or can assist in troubleshooting? =C2=A0 John C. Bohn Lancair 4P N28487 Direct (Cell)- 503-887-2933 ----------MB_8CAB56777DCD5A2_D44_918C_MBLK-M06.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8" Jeff L.

Great analysis.

Jeff


-----Original Message-----
From: Jeffrey Liegner, MD <liegner@embarqmail.com>
To: lml@lancaironline.net
Sent: Wed, 16 Jul 2008 6:51 am
Subject: [LML] Re: 4P Door seal pump operation at altitude

I've had this same problem for the last year.  Problems with maint= aining 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 ol= d.  My problem has been them same, up to altitude >20K, great PSI di= fferential (5psi), but after two hours-plus, the door cabin pressure starts=20= leaking out slowly, PSI differential decreases, cabin climbs above 10K and h= igher.  If I wait, I can see a sliver daylight between seal and frame.&= nbsp; I might even hear a slight wistle of leaking air (in flight, hard to t= ell).  I'd stuff cellophane into the gap during flight ...carried a role of kitchen plastic...to buy me more altitude flight time.<= /div>

The door seal works well (5psi held for >1hr) on the ground, holds i= ts inflation without leak for an hour or two, the pump works on the ground,=20= the light comes on the panel showing power delivered to the pump (but with e= ngine on, who can tell if pump is running), the valve works.  I was baf= fled 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 he= lp.
I occluded the pneumatic door valve/switch outflow to block leakage.&nb= sp; I then replaced the switch....no help.
I checked volts across the pressure sensor/switch, and found my panel L= ED would come on at 9V (as the seal pressure came down and the sensor starte= d 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/switc= h 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 des= pite having power applied.

I recently ordered a new pump and placed it in parallel with the old pu= mp during some ground tests.  Sure enough,=20 the new one came on and stayed on at 9V when the old one did not, when the s= ensor/switch was calling for pump, even up into the 12V range.

Today I replace the door pump on the mount.  Purchased from Lancai= r 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
w= ww.aerocraftparts.com
www.lancair.com=
michelleg@lancair.com=  




My door seal pump wor= ks fine on the ground i.e. it turns on and shuts off at the proper pressure=20= settings.  At altitude on a long trip over 3 or 4 hours the door seal l= ight comes on but the pump doesn=C2=B9t run.  I thought I fixed the pro= blem as I found the connectors in the overhead somewhat loose so I secured t= hem but now I=C2=B9m finding some arcing on the center (assuming power) post= and if I use a small screw driver and try to complete the connection the pu= mp barely wants to start (hard to complete circuit) it just arcs.  I= =C2=B9m getting good alignment between the door and airframe posts and what=20= I assume to be good spring pressure so I=C2=B9m speculating the temperature=20= of the wires/posts (at altitude is very cold) isn=C2=B9t providing good cond= uctivity to complete the circuit.  Has anyone else seen this or can ass= ist in troubleshooting?
 
John C. Bohn<= /B>
Lancair 4P=20= N28487
= Direct (Cell)- 503-887-2933

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