X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 06 Feb 2012 12:24:42 -0500 Message-ID: X-Original-Return-Path: Received: from hrndva-omtalb.mail.rr.com ([71.74.56.123] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with ESMTP id 5384698 for lml@lancaironline.net; Mon, 06 Feb 2012 10:23:35 -0500 Received-SPF: none receiver=logan.com; client-ip=71.74.56.123; envelope-from=Wolfgang@MiCom.net X-Original-Return-Path: X-Authority-Analysis: v=2.0 cv=HeuWv148 c=1 sm=0 a=MHZY6FYWMEQOp7S43i2QIw==:17 a=hKNyXSRXzacA:10 a=ttCsPuSJ-FAA:10 a=Ia-xEzejAAAA:8 a=ndVRne3UAAAA:8 a=5FIZSGrRAAAA:8 a=CjxXgO3LAAAA:8 a=ue5RmGVqIwnazdu_6ncA:9 a=L3UhcswTkUOIvQtmnagA:7 a=wPNLvfGTeEIA:10 a=VQWZxD7wvt0A:10 a=CVU0O5Kb7MsA:10 a=nrXl3C1RZZ4A:10 a=wR8WdYEwGqoA:10 a=EzXvWhQp4_cA:10 a=rC2wZJ5BpNYA:10 a=Whv8HLVs5OMA:10 a=1js-l5_995u4quQQFF8A:9 a=lRuw8jLgOEFSQkagUHoA:7 a=tXsnliwV7b4A:10 a=MHZY6FYWMEQOp7S43i2QIw==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.218.201.50 Received: from [74.218.201.50] ([74.218.201.50:1306] helo=lobo) by hrndva-oedge04.mail.rr.com (envelope-from ) (ecelerity 2.2.3.46 r()) with ESMTP id AC/56-01703-650FF2F4; Mon, 06 Feb 2012 15:23:02 +0000 X-Original-Message-ID: <005301cce4e3$35faf4d0$6701a8c0@lobo> From: "Wolfgang" X-Original-To: Subject: Fw: [LML] Re: 320/360 Hydraulic Pressure Switch X-Original-Date: Mon, 6 Feb 2012 10:22:59 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0050_01CCE4B9.4CEBB460" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_0050_01CCE4B9.4CEBB460 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I see the centering springs but what about the added spring, eyelet and = ball ? Where does that fit into the schematic ? I still don't like the idea of friction being the only thing keeping = spindle at it's end point. Sure, removing the springs will help but a = positive system to pressure the spindle back into it's required position = automatically as needed still seems prudent. Wolfgang ----- Original Message -----=20 From: Chris Zavatson=20 To: lml@lancaironline.net=20 Sent: Sunday, February 05, 2012 8:34 AM Subject: Re: [LML] Re: 320/360 Hydraulic Pressure Switch Several folks have been asking privately about the spool centering = springs mentioned below. This link contains both schematics and photos = showing how to revert a new pump back to the original 320/360 = functionality. =20 http://www.n91cz.com/Hydraulics/Pump-Unlock.pdf Chris Zavatson N91CZ 360std www.N91CZ.net From: Chris Zavatson To: lml@lancaironline.net=20 Sent: Wednesday, February 1, 2012 12:46 PM Subject: [LML] Re: 320/360 Hydraulic Pressure Switch Lorn, Had the temperature been 90 or 100 degrees your pressure would have been = even higher. In some of my hydraulics videos, you will see the 2,000 = psi gauge pegged on occasion during thermal heating tests. http://www.n91cz.com/Hydraulics/Lancair_Hydraulics.htm Your predicament of having to crack a hydraulic line is exactly what can = happen if the spool centers after pump shut down. I find that a = completely unacceptable design. Imagine taking off into IMC and the = gear won't come up. I had the opportunity to test out a pump in this = configuration last summer. Just as you experienced, I was able to = reproduce a complete lock up. =20 http://www.n91cz.com/Hydraulics/NewPumpLockUp_0001.wmv - hi res http://www.n91cz.com/Hydraulics/NewPumpLockUp_0002.wmv - low res After discussions with Lancair and Parker, I reverted the configuration = back to the original 320/360 config and all is good now. Only one side = can ever be pressurized at a time. Unfortunately due to employee = turn-over, no one currently at Parker or Lancair knows why the centering = springs were added. After reviewing the 320/360 system both agreed that = a system lock up is possible using replacement pumps currently sold = (108AMS32-CZZ-3V-14-08-Y). Parker sent me parts to revert three pumps = back to the original configuration.=20 The TRVs in our pumps are the lowest available -fixed setting of 2,500 = psi. This may be too high to protect some of our components. I have = run them up to 2,000 psi. In flight, I have seen 1,800 psi, descending = from 18k into the southwest deserts. Chris Zavatson N91CZ 360std www.N91CZ.net From: Lorn H Olsen To: lml@lancaironline.net=20 Sent: Wednesday, February 1, 2012 6:33 AM Subject: [LML] Re: 320/360 Hydraulic Pressure Switch Again, My Oildyne internal pressure switch came (set by Oildyne) at 1,500 PSI. = How do I know? I parked my plane on the ramp at Newport News, Va in the = evening. The temperature was 40=B0F. 3 days later, when I was going to = take off. The temperature was 80=B0F. I looked at my pressure gauges. = Both the up and down were at 1,500 PSI. I had to crack a nut in a = hydraulic line to release the pressure. The gear would not go up or = down, at this pressure. The emergency dump valve would not release, at = this pressure. The pump would not run at all, at this pressure. Now, I have Wolfgang's high pressure adapter in the system. It runs the = pump whenever the pressure is high on both the up and the down side. There is no speculation here. Just the facts, mam. -- Lorn H. 'Feathers' Olsen, MAA, ASMEL, ASES, Comm, Inst DynaComm, Corp., 248-345-0500, mailto:lorn@dynacomm.us LNC2, FB90/92, O-320-D1F, 1,800 hrs, N31161, Y47, SE Michigan -- For archives and unsub = http://mail.lancaironline.net:81/lists/lml/List.html ------=_NextPart_000_0050_01CCE4B9.4CEBB460 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I see the centering springs but what about the added spring, eyelet = and=20 ball ? Where does that fit into the schematic ?
 
I still don't like the idea of friction being the only thing = keeping=20 spindle at it's end point. Sure, removing the springs will help but a = positive=20 system to pressure the spindle back into it's required position = automatically as=20 needed still seems prudent.
 
Wolfgang
 
----- Original Message -----=20
From: Chris=20 Zavatson
Sent: Sunday, February 05, 2012 8:34 AM
Subject: Re: [LML] Re: 320/360 Hydraulic Pressure = Switch

Several folks have been asking privately = about the=20 spool centering springs mentioned below.  This link contains both=20 schematics and photos showing how to revert a new pump back=20 to the original 320/360 functionality. 
http://www.n91cz= .com/Hydraulics/Pump-Unlock.pdf
 
Chris Zavatson
N91CZ
360std


From: Chris Zavatson <chris_zavatson@yahoo.com>=
To: lml@lancaironline.net =
Sent: Wednesday, February 1, 2012 = 12:46=20 PM
Subject: [LML] Re: = 320/360=20 Hydraulic Pressure Switch

Lorn,
Had the temperature been 90 or 100 degrees = your=20 pressure would have been even higher.  In some of my hydraulics = videos, you=20 will see the 2,000 psi gauge pegged on occasion during thermal = heating=20 tests.
 
http://www.n91cz.com/Hydraulics/Lancair_Hydraulics.htm
 
Your predicament of having to crack a = hydraulic=20 line is exactly what can happen if the spool centers after pump shut = down. =20 I find that a completely unacceptable design.  Imagine taking off = into IMC=20 and the gear won't come up.  I had the opportunity to test out a = pump in=20 this configuration last summer.  Just as you experienced, I was = able to=20 reproduce a complete lock up. 
http://www.n91cz.com/Hydraulics/NewPumpLockUp_0001.wmv - hi = res
http://www.n91cz.com/Hydraulics/NewPumpLockUp_0002.wmv -=20 low res
 
After discussions = with=20 Lancair and Parker, I reverted the configuration back to the original 320/360 config and all is good = now.  Only one side can ever be pressurized at a time.  = Unfortunately=20 due to employee turn-over, no one currently at Parker or Lancair knows = why the=20 centering springs were added.  After reviewing the 320/360 system = both=20 agreed that a system lock up is possible using replacement pumps = currently sold=20 (108AMS32-CZZ-3V-14-08-Y).  Parker sent me parts to revert three = pumps back=20 to the original configuration. 
 
The TRVs in our pumps are the lowest available -fixed setting of = 2,500=20 psi.  This may be too high to protect some of our=20 components.  I have run them up to 2,000 psi.  = In=20 flight, I have seen 1,800 psi, descending from 18k into the southwest=20 deserts.
 
Chris Zavatson
N91CZ
360std
 
 

From: Lorn H Olsen=20 <lorn@dynacomm.us>
To:=20 lml@lancaironline.net
Sent:=20 Wednesday, February 1, 2012 6:33 AM
Subject: [LML] Re: 320/360 = Hydraulic=20 Pressure Switch

Again,

My Oildyne internal = pressure=20 switch came (set by Oildyne) at 1,500 PSI. How do I know? I parked my = plane on=20 the ramp at Newport News, Va in the evening. The temperature was 40=B0F. = 3 days=20 later, when I was going to take off. The temperature was 80=B0F. I = looked at my=20 pressure gauges. Both the up and down were at 1,500 PSI. I had to crack = a nut in=20 a hydraulic line to release the pressure. The gear would not go up or = down, at=20 this pressure. The emergency dump valve would not release, at this = pressure. The=20 pump would not run at all, at this pressure.

Now, I have = Wolfgang's high=20 pressure adapter in the system. It runs the pump whenever the pressure = is high=20 on both the up and the down side.

There is no speculation here. = Just the=20 facts, mam.


--
Lorn H. 'Feathers' Olsen, MAA, ASMEL, ASES, = Comm,=20 Inst
DynaComm, Corp., 248-345-0500, mailto:lorn@dynacomm.us
LNC2, = FB90/92,=20 O-320-D1F, 1,800 hrs, N31161, Y47, SE Michigan


--
For = archives and=20 unsub=20 http://mail.lancaironline.net:81/lists/lml/List.html




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