X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 11 Feb 2012 20:50:50 -0500 Message-ID: X-Original-Return-Path: Received: from nm4.bullet.mail.sp2.yahoo.com ([98.139.91.74] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with SMTP id 5391734 for lml@lancaironline.net; Sat, 11 Feb 2012 00:48:53 -0500 Received-SPF: none receiver=logan.com; client-ip=98.139.91.74; envelope-from=chris_zavatson@yahoo.com Received: from [98.139.91.66] by nm4.bullet.mail.sp2.yahoo.com with NNFMP; 11 Feb 2012 05:48:17 -0000 Received: from [72.30.22.36] by tm6.bullet.mail.sp2.yahoo.com with NNFMP; 11 Feb 2012 05:47:17 -0000 Received: from [127.0.0.1] by omp1066.mail.sp2.yahoo.com with NNFMP; 11 Feb 2012 05:47:17 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 778857.74218.bm@omp1066.mail.sp2.yahoo.com Received: (qmail 4294 invoked by uid 60001); 11 Feb 2012 05:47:17 -0000 DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=1/poQB0ruiZsJqVGVFqXKt9bj1EdS9iKFQPIctkxm976mBEI5PJU2E8NRH8+15XI0y8cmBbS457jMLefB3skbGI1NIw1Lmx0Ct8ckjrMZIHjSEYcVI8kTP7IQalqyXBAMca18q0xLcANXc5r57t7RBrtNiZ3r6gVY+AZASoG/vI=; X-YMail-OSG: KtWIrskVM1kvO3u3u8zWhnLVVB6oGILjhX2JbvBDcOqgc7j sSCGsXTSbbIJSbk98Eb0ivlaMern59LbitbNv5InJvXFMgqoeGv5xD8tYxXt c0nTC2HHIIMfksLsdkCVtU0XhPTcwY6RkkrYPpre9Ey4RhScCmepeEoE9tje Zu3ZWe6bVwl5yE7wlIDQ65CtaXwv3hW4Jd_1S08UQ5WXyY0zcqiH.6ZZ6X.I 7LvPcnKaCZR4xn8I2Np3oxqIhb30zfzqqlR4.RACv8qXkwg5kB8bqARR1GVQ mdHj3.I37P5Fe2FymU.Tivzb8hSmUQ1KXW8NDDSQ35em0c5cZVxUYzjR6pLF ruGQL7yxRYMixwi1euIsnPv8FGTE5jS3yb0aGcPcflXRpkP8a6s5zau5Zi89 jwFLDY9GKFYshd9xQEFEZq3ZqlaWdA93yrJnYA5jXl0Y9e7iuEnQgjbMbxtj BmP7OGKWn.L03Af9JwIQibA79Zm3jwuNYuyHMmuvje5NFrAD7bIfLru0qBEJ 6iAIB29cUB9RsefMalyZl_2R15gkp.2LKn7uJTqavCqchw93m4UAyk7.gbe_ kiyI0s4MfdTkBdsIXSwipbpTOYH0m1_bXB9VIV8m.DK13.KwcFWA53Jm.D4t 5 Received: from [99.152.23.138] by web36907.mail.mud.yahoo.com via HTTP; Fri, 10 Feb 2012 21:47:17 PST X-Mailer: YahooMailWebService/0.8.116.338427 References: X-Original-Message-ID: <1328939237.3081.YahooMailNeo@web36907.mail.mud.yahoo.com> X-Original-Date: Fri, 10 Feb 2012 21:47:17 -0800 (PST) From: Chris Zavatson Reply-To: Chris Zavatson Subject: Re: [LML] Re: 320/360 Hydraulic Pressure Switch X-Original-To: Lancair Mailing List In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-2114655128-2037344123-1328939237=:3081" ---2114655128-2037344123-1328939237=:3081 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Indeed, the springs=A0are very strong.=A0 You can sort of see that in the p= hotos.=A0 The wire diameter is quite hefty.=0AUsing=A0a brand new=A0013-70 = O-ring (for applications where the spool does not need to stay put), the sp= ring generates 4x the force required to move the spool.=0A=A0=0AIf your spo= ol is not staying in position:=0A1. Check for=A0and, if found, remove retur= n springs (for pumps purchased new or repaired by Oildyne since ~2003)=0A2.= Make sure the spool has an O-ring (two for symmetric spools)=0A3.=A0Make s= ure the spool has the 90 durometer O-ring=A0=0A=A0=A0=0AChris Zavatson=0AN9= 1CZ=0A360std=0Awww.N91CZ.net=0A=A0=0AFrom: Wolfgang =0A= To: lml@lancaironline.net =0ASent: Friday, February 10, 2012 7:26 AM=0ASubj= ect: [LML] Re: 320/360 Hydraulic Pressure Switch=0A=0AIf it takes that much= force to move the spindle against the O-rings then those springs must be p= retty darn strong. I find that dificult to accept.=0A=0AStill, that port wi= th the added spring, I believe it's a return port for excess hydraulic flui= d that can be used with a three port dump valve.=0A. . . but why the spring= if it's plugged anyway ?=0A=0AIf the ultimate answer is to remove the "ext= ra" springs, then let's demonstrate that by testing a pump with the springs= under pressure, heat, AND simulated engine vibration. Short of that, this = failure mode remains a question.=0A=0AWolfgang=0A=0A=A0=0AFrom: Chris Zavat= son =0ASender: =0ASubje= ct: Re: [LML] Fw: [LML] Re: 320/360 Hydraulic Pressure Switch =0ADate: Wed,= 08 Feb 2012 08:05:15 -0500 =0ATo: lml@lancaironline.net =0AWolfgang,=0ATh= e ball and spring go in the port labeled "Cavity "E" Back-Pressure".=A0 Thi= s is the pipe plug that sits in between the two output ports.=0A=A0=0AYou m= ight consider securing the dump valve with a secondary locking feature.=A0 = It too relies on friction alone to stay in position.=A0 Seriously, given th= e force it takes to move the spool, if mine were not staying put, I would= =A0want to know why.=A0 =0A=A0=0AFrom previous measurements:=0AUsing O-ring= =A0013-70 requires 30 g's to move the spool.=0AUsing O-ring=A0013-90 requir= es 70 g's to move the spool. =0AThe 013-90 is=A0specified for pumps with ba= ck pressure circuits such as we have.=0A=A0=0AChris Zavatson=0AN91CZ=0A360s= td=0Awww.N91CZ.net=0A=A0=0AFrom: Wolfgang =0ATo: lml@la= ncaironline.net =0ASent: Monday, February 6, 2012 9:24 AM=0ASubject: [LML] = Fw: [LML] Re: 320/360 Hydraulic Pressure Switch=0A=0AI see the centering sp= rings but what about the added spring, eyelet and ball ? Where does that fi= t into the schematic ?=0A=0AI still don't like the idea of friction being t= he 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 req= uired position automatically as needed still seems prudent.=0A=0AWolfgang= =0A=0A----- Original Message ----- =0AFrom: Chris Zavatson =0ATo: lml@lanca= ironline.net =0ASent: Sunday, February 05, 2012 8:34 AM=0ASubject: Re: [LML= ] Re: 320/360 Hydraulic Pressure Switch=0ASeveral folks have been asking pr= ivately about the spool centering springs mentioned below.=A0 This link con= tains both schematics and photos=A0showing how to revert=A0a new pump back = to=A0the original 320/360 functionality.=A0 =0Ahttp://www.n91cz.com/Hydraul= ics/Pump-Unlock.pdf=0A=0AChris Zavatson=0AN91CZ=0A360std=0Awww.N91CZ.net=0A= From: Chris Zavatson =0ATo: lml@lancaironline.net= =0ASent: Wednesday, February 1, 2012 12:46 PM=0ASubject: [LML] Re: 320/360= Hydraulic Pressure Switch=0A=0ALorn,=0AHad the temperature been 90 or 100 = degrees your pressure would have been even higher.=A0 In some of my hydraul= ics videos, you will=A0see the 2,000 psi gauge pegged on occasion during th= ermal heating tests.=0A=0Ahttp://www.n91cz.com/Hydraulics/Lancair_Hydraulic= s.htm=0A=0AYour predicament=A0of having to crack a hydraulic line is exactl= y what can happen if the spool centers after pump shut down.=A0 I find that= a completely unacceptable design.=A0 Imagine taking off into IMC and the g= ear won't come up.=A0 I had the opportunity to test out a pump in this conf= iguration last summer.=A0 Just as you experienced, I was able to reproduce = a complete lock up.=A0 =0Ahttp://www.n91cz.com/Hydraulics/NewPumpLockUp_000= 1.wmv=A0- hi res=0Ahttp://www.n91cz.com/Hydraulics/NewPumpLockUp_0002.wmv= =A0- low res=0A=0AAfter discussions with Lancair and Parker, I reverted the= configuration back to the original 320/360 config and all is good now.=A0 = Only one side can ever be pressurized at a time.=A0 Unfortunately due to em= ployee turn-over, no one currently at Parker or Lancair knows why the cente= ring springs were added.=A0 After reviewing the 320/360 system both agreed = that a system lock up is possible using replacement pumps currently sold (1= 08AMS32-CZZ-3V-14-08-Y).=A0 Parker sent me parts to revert three pumps back= to the original configuration.=A0=0A=A0=0AThe TRVs in our pumps are the lo= west available -fixed setting of 2,500 psi.=A0 This may be too high=A0to pr= otect=A0some of our components.=A0 I=A0have=A0run them up=A0to 2,000 psi.= =A0 In flight, I have seen 1,800 psi, descending from 18k into the southwes= t deserts.=0A=0AChris Zavatson=0AN91CZ=0A360std=0Awww.N91CZ.net=0A=0A=0AFro= m: Lorn H Olsen =0ATo: lml@lancaironline.net =0ASent: Wed= nesday, February 1, 2012 6:33 AM=0ASubject: [LML] Re: 320/360 Hydraulic Pre= ssure Switch=0AAgain,My Oildyne internal pressure switch came (set by Oildy= ne) at 1,500 PSI. How do I know? I parked my plane on the ramp at Newport N= ews, Va in the evening. The temperature was 40=B0F. 3 days later, when I wa= s going to take off. The temperature was 80=B0F. I looked at my pressure ga= uges. Both the up and down were at 1,500 PSI. I had to crack a nut in a hyd= raulic line to release the pressure. The gear would not go up or down, at t= his 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 hig= h 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 t= he facts, mam.--Lorn H. 'Feathers' Olsen, MAA, ASMEL, ASES, Comm, InstDynaC= omm, Corp., 248-345-0500, mailto:lorn@dynacomm.usLNC2, FB90/92, O-320-D1F, = 1,800 hrs, N31161, Y47, SE Michigan ---2114655128-2037344123-1328939237=:3081 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
Indeed, the springs&nb= sp;are very strong.  You can sort of see that in the photos.  The= wire diameter is quite hefty.
Using a brand n= ew 013-70 O-ring (for applications where the spool does not need to st= ay put), the spring generates 4x the force required to move the spool.
 
If your spool is not= staying in position:
1. Check for an= d, if found, remove return springs (for pumps purchased new or repaired by = Oildyne since ~2003)
2. Make sure the spo= ol has an O-ring (two for symmetric spools)
3. Make sure th= e spool has the 90 durometer O-ring 
  <= /div>
Chris Zavatson
N91CZ
360std
 
From:= Wolfgang <Wolfgang@MiCom.net>
To: lml@lancaironline.net
Sent: Friday, February 10, 2012 7:26 AM
Subject: [LML] Re: 320/360 Hydra= ulic Pressure Switch
If it takes that much force to move the spindle = against the O-rings then those springs must be pretty darn strong. I find t= hat dificult to accept.
 
Still, that port with the added spring, I believ= e it's a return port for excess hydraulic fluid that can be used with a thr= ee port dump valve.
. . . but why the spring if it's plugged anyway = ?
 
If the ultimate answer is to remove the "extra" = springs, then let's demonstrate that by testing a pump with the springs und= er pressure, heat, AND simulated engine vibration. Short of that, this fail= ure mode remains a question.
 
Wolfgang

 
From: Chris Zavatson = <chris_zavatson@yahoo.com>
Sender: <marv@lancai= ronline.net>
Subject: Re: [LML] Fw: [LML] Re: 320/360 Hydra= ulic Pressure Switch
Date: Wed, 08 Feb 201= 2 08:05:15 -0500
To: lml@lancaironline.net
Wolfgang,
The ball and spring go in the port labeled "Cavity "E" Back-Pres= sure".  This is the pipe plug that sits in between the two output port= s.
 
<= SPAN style=3D"RIGHT: auto" id=3Dyiv326657542yui_3_2_0_17_132865856497272>Yo= u might consider securing the dump valve with a secondary locking feature.&= nbsp; It too relies on friction alone to stay in position.  Seriously,= given the force it takes to move the spool, if mine were not staying put, = I would want to know why. 
 
From previous measur= ements:
Using O-ring 013-70 requires 30 g's= to move the spool.
Using O-ring 013-90 requires 70 g's= to move the spool.=20
The 013-90 is specified for pumps with back= pressure circuits such as we have.
 
Chris Zavatson
N91CZ
360std
 
From: Wolfgang <Wolfgang@MiCo= m.net>
To: lml@lancaironline.net
Sen= t: Monday, February 6, 2012 9:24 AM
Subject:<= /B> [LML] Fw: [LML] Re: 320/360 Hydraulic Pressure Switch
<= WBR>
I see the centering springs but what about the a= dded spring, eyelet and ball ? Where does that fit into the schematic ?
 
I still don't like the idea of friction being th= e 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 requ= ired position automatically as needed still seems prudent.
 
Wolfgang
 
----- Original Message -----=20
Sent: Sunday, Febru= ary 05, 2012 8:34 AM
Subject: Re: [LML] = Re: 320/360 Hydraulic Pressure Switch
Several folks have been asking privately about the spool centering spr= ings mentioned below.  This link contains both schematics and photos&n= bsp;showing how to revert a new pump back 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@lancaironl= ine.net
Sent: Wednesday, February 1, 2012 12:46 PM<= BR>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 h= eating tests.
 
http://www.n91cz.com/Hydraulics/Lancair_Hydraulics.htm
 
Your predicament of having to crack a hydra= ulic line is exactly what can happen if the spool centers after pump shut d= own.  I find that a completely unacceptable design.  Imagine taki= ng 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 experi= enced, I was able to reproduce a complete lock up. 
http://www.n91cz.com/Hydraulics/NewPumpLockUp_0001.wmv - hi res
http://www.n91cz.com/Hydraulics/NewPumpLockUp_00= 02.wmv - low res
 
After discussions wi= th Lancair and Parker, I reverted the configuration back to the original 320/360 config and all is good now.&= nbsp; 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 curre= ntly sold (108AMS32-CZZ-3V-14-08-Y).  Parker sent me parts to revert t= hree pumps back to the original configuration. 
 
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 component= s.  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
 
 
From: Lorn H= Olsen <lorn@dynacomm.us>
To: lml@lancaironlin= e.net
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 ram= p at Newport News, Va in the evening. The temperature was 40=B0F. 3 days la= ter, 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.No= w, 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.T= here is no speculation here. Just the facts, mam.--Lorn= H. 'Feathers' Olsen, MAA, ASMEL, ASES, Comm, InstDynaComm, Corp., 248= -345-0500, mailto:lorn@dynacomm.usLNC2= , FB90/92, O-320-D1F, 1,800 hrs, N31161, Y47, SE Michigan
<= /DIV>
---2114655128-2037344123-1328939237=:3081--