X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 05 Apr 2011 00:40:18 -0400 Message-ID: X-Original-Return-Path: Received: from web36908.mail.mud.yahoo.com ([209.191.85.76] verified) by logan.com (CommuniGate Pro SMTP 5.4c2) with SMTP id 4932400 for lml@lancaironline.net; Mon, 04 Apr 2011 16:03:34 -0400 Received-SPF: none receiver=logan.com; client-ip=209.191.85.76; envelope-from=chris_zavatson@yahoo.com Received: (qmail 5753 invoked by uid 60001); 4 Apr 2011 20:02:57 -0000 DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:X-YMail-OSG:Received:X-Mailer:References:Date:From:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=ymvom7fjMNVnMg6WF0QogCGA9haeYq3IJbvx3FW0FT9Zgro4XdcLU1zhg3fhCzhosSgEsQzt1WOlZbKt0M7a+KVINmV+06FGpLHmUH/mBpMWhdb/ZIamEdTwlfyVvpBfCNB08idRiuIaf+i9mxeC5uJGuxnyIkHsuzsvRim10uY=; X-Original-Message-ID: <173721.95700.qm@web36908.mail.mud.yahoo.com> X-YMail-OSG: iyUiOAsVM1l55Y86UXHnZpklV5of80GPo7IZGUz8AmNfgJR unfoZsPZHa1qiAuifLlF04iik3MhUgQlYF79u3tWouMZ5L9yyKGRs_y4ARhW 9.Zn745Y7_GD6SRIY7e9nLCPzsSSCdrmldujBQTu_E5KxCzWf_fdOhGciHT4 T48WBycQheLB0sNOF3MxSLHMPZYi1FlZmtOlHuK1U2y04xeWT7QKWcX4dGcl LR0amq4WTg0FK.W8ygHgUU0VnpUnWSciTwLytV8vpD3k3Px2xfXuObFrf2su kuY4FPFwpxa8YJBuQv1GSJBiqSfmIXG6RJbQlQ_iqRWI0nIoVy4MROE2gmLs RfjhcghXSFduQ9kH_He5nIf2aQQqkThoavzQVDed90r_CePrNC0qv3XCaaRq r_XQtVOVhN.et4rH5 Received: from [12.130.164.194] by web36908.mail.mud.yahoo.com via HTTP; Mon, 04 Apr 2011 13:02:56 PDT X-Mailer: YahooMailRC/559 YahooMailWebService/0.8.109.295617 References: X-Original-Date: Mon, 4 Apr 2011 13:02:56 -0700 (PDT) From: Chris Zavatson Subject: Re: [LML] LNC2 Gear Hydraulics X-Original-To: Lancair Mailing List In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-1347512133-1301947376=:95700" --0-1347512133-1301947376=:95700 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Tom,=0ACould you please elaborate on how a centered spool eliminates the pr= oblems =0Alisted? =0A=0AHistorically, a centered spool is to be avoided.=A0= It will allow the system to =0Alock up with thermal heating and or leaks f= rom the charged side to the uncharged =0Aside?=A0 (see jpeg=A0"LB" down neu= tral) How does=A0the new design deal with these =0Afailure modes?=0AThe jpe= gs showed the current system as is.=A0 Do you have any representing your = =0Anew configuration?=0A=A0=0AChris Zavatson=0AN91CZ=0A360std=0Awww.N91CZ.n= et=0A=0A=0A=0A________________________________=0AFrom: TOM GARDINER =0ATo: lml@lancaironline.net=0ASent: Mon, April 4, 2011 4:41:38 = AM=0ASubject: [LML] LNC2 Gear Hydraulics=0A=0A=0A=0A=0A=0A=0A=0A___________= _____________________=0AFrom: TOM GARDINER =0ATo: lml@lan= caironline.net=0ASent: Sat, April 2, 2011 8:52:18 PM=0ASubject: Fw: LNC2 Ge= ar Hydraulics=0A=0A=0AFolks,=0A=0AI have had various requests from people t= o post the attachments that I thought =0Ahad already made it to the forum f= rom my original post.=A0 But as the moderator =0Akindly informed me,=A0my a= ttachments were way too large.=A0 So=A0hopefully this =0Aslideshow will mak= e it.=A0 Nice tool - thanks Marvin.=A0 =0A=0A=0A=0Ahttp://www.berkut13.com/= 108%20Startup%20Instructions.pdf=0Ahttp://www.swagelok.com/downloads/WebCat= alogs/EN/ms-02-331.pdf=0Ahttp://oemys-performance.com/media/autopark%20pump= %20108a.pdf=0Ahttp://www.berkut13.com/108%20RV%20adjusting%20and%20cleaning= .pdf=0A=0A=0AA few items I failed to mention in my earlier post that came t= o mind after =0Areading Chris Zavaston's excellent post.=A0 The article lis= ted the failure modes =0Aof the hydraulic system as follows:=0A=0AReversed = Spool ValveThe reversed spool is a common problem.=A0 The standard =0Aadapt= er is always configured this way and needs to be reversed=0A=A0=0ADrifting = Spool Valve=0AThe drifing spool is mitigated by the centering springs when = used with the =0Asymmetric spool.=A0 =0A=0A=A0=0ALeaks, internal and extern= al=0AThe symmetric spool has two O rings instead of one.=A0=A0 The O rings = are fitted on =0Aeach end and allows for a better seal and better allignmen= t of the spool while =0Amoving inside the adapter barrel.=A0 There will als= o be less wear as a =0Aconsequence.=A0 Transmission fluid may be used in pl= ace of hydraulic fluid which =0Ahas better lubricating qualities=0A=A0=0ACo= ntamination=0AKeep it clean, clean, clean!=A0=0A=A0=0ARegarding the 3 way v= alve, I decided to go with this since it is the only =0Areliable way to ext= end the gear without power.=A0 As noted in previous posts there =0Aare fail= ure modes that will prevent the gear comming down in normal operation =0Aev= en after operating the 2 way dump valve.=A0 Using a circuit to momentarily = short =0Aout the down pressure switch will allow the pump to work but I don= t want=A0to find =0Aout that the problem has been lurking in my system when= the power fails.=A0 The =0Avalve I used is the same as the one specified f= or the Legacy.=A0 The Legacy uses a =0Avent to the tank=0A=0A=0A=0A=A0=0A--= --- Forwarded Message ----=0AFrom: TOM GARDINER =0ATo: La= ncair Mailing List =0ASent: Sun, March 27, 2011 11:2= 1:12 PM=0ASubject: LNC2 Gear Hydraulics=0A=0A=0A=0A=0AFolks,=0A=A0=0AI thou= ght I would take some time here to outline my recent experience with the = =0Aparker oildyne pump so that it would save some of you the same time and = expense =0Ai have had to deal with recently.=A0 My pump had been sitting in= the aircraft for =0Aa number of years through the early construction phase= without exercise.=A0 Once=A0I =0Abegan swinging the gear and flying I expe= rienced various issues:=0A=A0=0A=091. Gear would not retract - despite oper= ation of the dump valve=A0=0A=092. Gear would not lower unless dump valve w= as actuated=0A=093. Pump would screech and make various noises =0A=094. Pum= p would turn on and off frequently during flight=0A=A0=0AAfter experiencing= all of these issues I decided to make it my mission to learn =0Aas much ab= out the system and eliminate all of the failure modes.=A0=A0 Lessons =0Alea= rned:=0A=A0=0A=091. The pump has many applications in the marine industry f= or which there is =0Asome=A0excellent documentation=0A=092. The two way dum= p valve supplied with the kit is poor quality and cannot be =0Atrusted (can= leak internally and externally)=0A=093. It is a very good idea to install = pressure gauges in both up and down =0Ahydraulic lines=0A=094. The original= pump is slow to raise and lower the gear=0A=095. Nobody knows more about t= he equipment than Parker/Oildyne=0A=096. Heat will cause pressure increases= in the lines to the point that the =0Apressure switches will drop out=0A= =097. Seals inside the pump will eventually leak through wear and tear espe= cially =0Aafter sitting for a long period=0A=098. There are numerous failue= modes to the system, the goal is to eliminate as =0Amany of them as possib= le=0A=A0=0AFollowing 2 instances of not being able to raise my gear in flig= ht I had had =0Aenough.=A0 After studying all of the related posts on this = site I then elected to =0Acall Oildyne.=A0 The people there were kind enoug= h to share with me their =0Aengineering drawings and their recommendation o= f the correct configuration for =0Athe pump internals for the LNC2 applicat= ion.=A0 Contrary to some of the posts to =0ALML the preferred spool type is= a symmetrical one that is centered using two =0Aadditional springs.=A0 The= attached drawings provide a good understanding of how =0Athe spool, check = valves and relief valves work.=A0 Armed with the data=A0=A0I set =0Aabout m= odifying my hydraulic system=A0as follows:=0A=A0=0A=091. Removed the origin= al pump adapter from the pump motor - Parker p/n781021=0A=092. Removed the = relief valves from the pump adapter and installed on=A0a new =0Aadapter - P= arker p/n 781047=0A=093. Replaced the gear pump module for the high output = upgrade - Parker p/n =0A634218=A0=0A=094. Replaced the dump valve with a hi= gh quality swagelok 3 way valve that dumps =0Ato the tank B-42XHF2=3DBKB=0A= =095. Replaced one of the pressure switches for another (was replaced under= =0Awarranty - had a 500psi hysteresis)=0A=096. Installed a small pressure = gauge for diagnostic use=0A=097. Installed a new fluid reservoir. New desig= n does not=A0have the mounting hole =0Ain the bottom=0AA 781021 can be conv= erted to a 781047 by performing the following steps=0A=A0=0A=091. Remove th= e=A0asymmetric spool in the pump adapter and replace it with the =0Asymmetr= ic one along with the two centering springs=0A=092. Remove center relief va= lve as shown in drawing - it is unnecessary =0A=A0=0ANet results:=0A=A0=0A= =091. All gear legs move together and at about the same rate=0A=092. No scr= eeching - sounds smooth with positive cut off - I believe the center =0Arel= ief valve to be responsible for the occasional screeching =0A=0A=093. Emerg= ency dump valve dumps pressure on both sides of the pump to zero with =0Are= turn to the tank=0A=094. No internal leaks -=A0=A0Hence no cycling of the p= ump in flight=0A=095. 100% reliability on gear operations =0AAll mods to pu= mp done for $250=0A=A0=0A=A0=0A=A0=0ANotes:=0A=A0=0ATo inspect the check va= lve poppet as a possible leak down cause, remove the hex =0Aplug, on whiche= ver side of the power unit is having the problem. Inside there is =0Athe sp= ring and the poppet. =A0Check the rubber face seal of the poppet for any = =0Achips which might be embedded. On a rare occasion the face seal itself, = which =0Ahas a 'stepped' design, may delaminate, which can cause a leak. = =A0When finished =0Adoing all this, retorque the hex plug to 450-600 in-lbs= .=0A=A0=0AParts can be sourced from =0AWestern Fluid Power, 2759 South 300 = West, Suite H, Salt Lake City, Utah 84115. =0ATalk to Boyd Ottenstein at 80= 1-486-6500 =0A=0A=A0=0AOildyne Sales contact =0Alarry.fern@parker.com=0A=0A= =A0=0ATom Gardiner=0ALNC2 826CT --0-1347512133-1301947376=:95700 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
=0A
=0A

Tom,

=0A

Could you please elaborate o= n how a centered spool eliminates the problems listed?

=0A

Historically, a centered spool is to be avoided.  = It will allow the system to lock up with thermal heating and or leaks from = the charged side to the uncharged side?  (see jpeg "LB" dow= n neutral) How does the new design deal with these failure mode= s?

=0A

= The jpegs showed the current system as is.&nb= sp; Do you have any representing your new configuration?

=0A

 

=0A

Chris Zavatson

=0A

N91CZ

=0A

360std

= =0A

www.= N91CZ.net

=0A

=0A
=0A<= HR SIZE=3D1>=0AFrom: TOM GA= RDINER <n20087@yahoo.com>
To:= lml@lancaironline.net
S= ent: Mon, April 4, 2011 4:41:38 AM
Subject: [LML] LNC2 Gear Hydraulics

=0A=
= =0A

=0A

=0A
=0A
=0AFrom: TOM GARDINER= <n20087@yahoo.com>
To: lml@lancaironline.net
Sent: Sat, April 2, 2011 8:52:18 PM
Subject: Fw: LNC2 Gear Hydraulics

=0A
=0A
=0A=0A=0A=
Folks,
=0A
 
=0A
I have had various requests fr= om people to post the attachments that I thought had already made it to the= forum from my original post.  But as the moderator kindly informed me= , my attachments were way too large.  So hopefully this slid= eshow will make it.  Nice tool - thanks Marvin. 
=0A
&n= bsp;
=0A
 
=0A
http://www.berkut13.com/108%20Startup= %20Instructions.pdf
=0A
http://www.swagelok.com/downloads/WebCatal= ogs/EN/ms-02-331.pdf
=0A
http://oemys-performance.com/media/autopa= rk%20pump%20108a.pdf
http://www.berkut13.com/108%20RV%20adjusting%20and%= 20cleaning.pdf
=0A
 
=0A
 
=0A
A few items I failed to m= ention in my earlier post that came to mind after reading Chris Zavaston's = excellent post.  The article listed the failure modes of the hydraulic= system as follows:
=0A
 
=0A
=0A

= Reversed Spool Valve

=0A
The reversed spool is a common problem.  The standard adapter is a= lways configured this way and needs to be reversed
=0A=

 

=0A

Drifting Sp= ool Valve

=0A

The drifing spool is mitig= ated by the centering springs when used with the symmetric spool.  =0A

 

=0A

Leaks, = internal and external

=0A

The symmetric spool has two O rings instead of one.  = The O rings are fitted on each end and allows for a better seal and better= allignment of the spool while moving inside the adapter barrel.  Ther= e will also be less wear as a consequence.  Transmission fluid may be = used in place of hydraulic fluid which has better lubricating qualities

=0A

 =0A

Contami= nation

=0A

Keep it clean, clean, = clean! 

=0A

 

=0A

= Regarding the 3 way valve, I decided to go with this since = it is the only reliable way to extend the gear without power.  As note= d in previous posts there are failure modes that will prevent the gear comm= ing down in normal operation even after operating the 2 way dump valve.&nbs= p; Using a circuit to momentarily short out the down pressure switch will a= llow the pump to work but I dont want to find out that the problem has= been lurking in my system when the power fails.  The valve I used is = the same as the one specified for the Legacy.  The Legacy uses a vent = to the tank

=0A
 
=0A
 
=0A 
=0A
=0A
----- Forwarded Me= ssage ----
From: TOM GAR= DINER <n20087@yahoo.com>
To:<= /SPAN> Lancair Mailing List <lml@lancaironline.net>
Sent: Sun, March 27, 2011 11:21:12 PM=
Subject: LNC2 Gear Hydr= aulics

=0A
=0A
=0A
=0A

=0A
=0A
=0A
=0A

Folks,

=0A

 

=0A

I thought I would take some ti= me here to outline my recent experience with the parker oildyne pump so tha= t it would save some of you the same time and expense i have had to deal wi= th recently.  My pump had been sitting in the aircraft for a number of= years through the early construction phase without exercise.  Once&nb= sp;I began swinging the gear and flying I experienced various issues:

=0A

 

=0A
    =0A
  1. =0A
    Gear would not retract - despite= operation of the dump valve 
    2. =0A
  2. =0A
    Gear would n= ot lower unless dump valve was actuated
    3. =0A
  3. =0A
    Pump wo= uld screech and make various noises
    4. =0A
  4. =0A
    Pump woul= d turn on and off frequently during flight
=0A

 

=0A

After experiencing all of these issues I decided to make it my m= ission to learn as much about the system and eliminate all of the failure m= odes.   Lessons learned:

=0A

 

=0A
    =0A<= LI>=0A
    The pump has many applications in the marine industry for which ther= e is some excellent documentation
    =0A
  1. =0A
    The two = way dump valve supplied with the kit is poor quality and cannot be trusted = (can leak internally and externally)
    2. =0A
  2. =0A
    It is a v= ery good idea to install pressure gauges in both up and down hydraulic line= s
    3. =0A
  3. =0A
    The original pump is slow to raise and lower = the gear
    4. =0A
  4. =0A
    Nobody knows more about the equipment = than Parker/Oildyne
    5. =0A
  5. Heat will cause pressure increases in the lines to th= e point that the pressure switches will drop out
    6. =0A
  6. =0A
    Seal= s inside the pump will eventually leak through wear and tear especially aft= er sitting for a long period
    7. =0A
  7. =0A
    =0A
    There are numerou= s failue modes to the system, the goal is to eliminate as many of them as p= ossible
=0A

 

=0A

Following 2 instan= ces of not being able to raise my gear in flight I had had enough.  Af= ter studying all of the related posts on this site I then elected to call O= ildyne.  The people there were kind enough to share with me their engi= neering drawings and their recommendation of the correct configuration for = the pump internals for the LNC2 application.  Contrary to some of the = posts to LML the preferred spool type is a symmetrical one that is centered= using two additional springs.  The attached drawings provide a good u= nderstanding of how the spool, check valves and relief valves work.  A= rmed with the data  I set about modifying my hydraulic system&nbs= p;as follows:

=0A

 

=0A
    =0A
  1. =0A
    Removed the or= iginal pump adapter from the pump motor - Parker p/n781021
    =0A
  2. =0A
    Removed the relief valves from the pump adapter and installed o= n a new adapter - Parker p/n 781047
    3. =0A
  3. =0A
    Replac= ed the gear pump module for the high output upgrade - Parker p/n 634218&nbs= p;
    4. =0A
  4. =0A
    Replaced the dump valve with a high quality = swagelok 3 way valve that dumps to the tank B-42XHF2=3DBKB
    =0A
  5. =0A
    Replaced one of the pressure switches for another (was replaced= under warranty - had a 500psi hysteresis)
    6. =0A
  6. =0A
    Inst= alled a small pressure gauge for diagnostic use
    7. =0A
  7. =0A=
    Installed a new fluid reservoir. New design does not have the mountin= g hole in the bottom
=0A

A 781021 can be converted to a= 781047 by performing the following steps

=0A

 

=0A<= OL>=0A
  • =0A
    Remove the asymmetric spool in the pump adapter and repl= ace it with the symmetric one along with the two centering springs
    • =0A
  • =0A
    Remove center relief valve as shown in drawing - it is = unnecessary
    • =0A

     

    =0A

    Net results:=

    =0A

     

    =0A
      =0A
    1. =0A
      All gear legs move together and = at about the same rate
      2. =0A
    2. =0A
      No screeching - sounds s= mooth with positive cut off - I believe the center relief valve to be respo= nsible for the occasional screeching
      3. =0A
    3. =0A
      Emergency= dump valve dumps pressure on both sides of the pump to zero with return to= the tank
      4. =0A
    4. =0A
      No internal leaks -  Hence = no cycling of the pump in flight
      5. =0A
    5. =0A
      100% reliabili= ty on gear operations
    =0A

    All mods to pump done for $2= 50

    =0A

     

    =0A

     

    =0A

    =  

    =0ANot= es:

    =0A

     

    =0A

    To inspect the check valve poppet as= a possible leak down cause, remove the hex plug, on whichever side of the = power unit is having the problem. Inside there is the spring and the poppet= .  Check the rubber face seal of the poppet for any chips which might = be embedded. On a rare occasion the face seal itself, which has a 'stepped'= design, may delaminate, which can cause a leak.  When finished doing = all this, retorque the hex plug to 450-600 in-lbs.

    =0A

     <= /P>=0A

    =0A=0A=0A=0A=0A=0A=
    =0A

    Parts can be sourced from

    = =0A

    Western Fluid Po= wer, 2759 South 300 West, Suite H, Salt Lake City, Utah 84115. Talk to Boyd= Ottenstein at 801-486-6500

    =
    =0A

     

    =0A

    Oildyne Sales contact

    =0A

    larry.fern@parker.com

    =0A

     

    =0A

    Tom G= ardiner

    =0A

    LNC2 826CT

    =0A

     

    --0-1347512133-1301947376=:95700--