X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 12 Mar 2009 19:30:05 -0400 Message-ID: X-Original-Return-Path: Received: from [64.12.137.6] (HELO imo-m25.mail.aol.com) by logan.com (CommuniGate Pro SMTP 5.2.13) with ESMTP id 3545166 for lml@lancaironline.net; Thu, 12 Mar 2009 11:09:20 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.137.6; envelope-from=Sky2high@aol.com Received: from Sky2high@aol.com by imo-m25.mx.aol.com (mail_out_v39.1.) id q.c57.51205fd8 (39329) for ; Thu, 12 Mar 2009 11:08:46 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Thu, 12 Mar 2009 11:08:47 EDT Subject: Re: [LML] Re: oil cooling/Vernatherm X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1236870527" X-Mailer: AOL 9.1 sub 5003 X-Spam-Flag:NO -------------------------------1236870527 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Randy, Oh, I forgot. I also replaced the Vernatherm, but I don't remember technical details of the testing (a long story involving a flash fire - best told in a bar). I believe the chamber that the Vernatherm operates in is such that, when cold, allows oil to bypass being sent to the cooler. When hot, the extension of the device shuts the bypass opening. Thus, if the Vernatherm does not fully extend when hot, the bypass is not sealed and uncooled oil would be returned to the system. Here is one example of test results: _http://www.vansairforce.com/community/showthread.php?t=32763_ (http://www.vansairforce.com/community/showthread.php?t=32763) Here is some interesting info, click on tech data: _http://www.rostravernatherm.com/oil-valves.htm_ (http://www.rostravernatherm.com/oil-valves.htm) Here is a more interesting read: _http://www.sacskyranch.com/eng18.htm_ (http://www.sacskyranch.com/eng18.htm) Scott. In a message dated 3/12/2009 9:35:08 A.M. Central Daylight Time, randylsnarr@yahoo.com writes: Scott, I was thinking the same thing and am making plans to "redo" my oil cooler to cowl connection and make it nice and smooth. That will happen after I verify the vernatherm is doing what is supposed to... I pulled out the vernatherm the other day and put it in boiling water to see what it would do. I admit I really do not understand how it works but the spring loaded end got about 1/8" longer when going from room temp to 212 F. Does that mean it is working? If anyone knows if this is good or bad, please pipe in... Thanks for the feedback! Randy Snarr --- On Tue, 3/10/09, Sky2high@aol.com wrote: From: Sky2high@aol.com Subject: [LML] Re: oil cooling To: lml@lancaironline.net Date: Tuesday, March 10, 2009, 8:36 PM Randy, My large sharp edged NACA duct is poorly placed on the left rearward side of cowling. It enters a short flexible 3" smooth rubber sleeve (plumber's sleeve) and then to a plenum above the small SW oil cooler mounted to the fire wall. The bottom is open to the lower cowl. I climb at about 135 KIAS and see cylinders occasional reach 400 degrees on a hot day while the oil stays at 180. In cruise in 30-40F temps, I must at least partially close the door between the NACA and the cooler. Recently, in 10C temps, I had to completely close the door to keep the oil temps about 180. In the pattern at 100 KIAS I will see the oil go 190F or even 200F on hot days because of lack of air thru the cooler. It wasn't always that way. When I had high oil temps, I tried a special cooler air exit to assist, no help.. Another was to try exiting thru shark gills on the side of the cowl, no help. I temporarily attached a scoop to force more air in the duct, no help. I finally discovered that the air was backed up in the NACA duct plenum (or chamber), thus cutting off air flow. I used Micro to smoothly shape the chamber, thus directing the air into its 3" outlet (no more dead corners) with the results detailed above. Good Luck, Scott Krueger AKA Grayhawk Lancair N92EX IO320 SB 89/96 Aurora, IL (KARR) In a message dated 3/9/2009 12:41:32 P.M. Central Daylight Time, marv@lancair.net writes: Posted for randy snarr : All, Thanks for the good suggestions on the oil cooler. I flew again today and my oil temps are at 208 F flying in 35 f air. They will be 215 or 220 this summer. I will try a few solutions that do not need to cut the cowl. I will most likely make a duct to carry the exhaust air from the oil cooler down to the lower aft part of the cowl. I have also heard that the aft vertical edge of the naca opening should be shaped like an air foil. Mine is flat and fairly sharp. The easiest way to test will to be construct a piece to give it a little airfoil made from balsa or foam taped in place and flight tested. If that does not work, I will make a duct from the cooler to the low pressure area on the bottom of the cowl and lastly would be a small lip on the bottom of the cowl aft. every producton airplane I have seen with an opening on the bottom of the cowl has 45 deg lip to create a low pressure area. I should have done that before I painted.... I will post my findings when I get them. Randy Snarr N694RS -- SFor archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html ____________________________________ A Good Credit Score is 700 or Above. _See yours in just 2 easy steps!_ (http://pr.atwola.com/promoclk/100126575x1219671244x1201345076/aol?redir=http://www. freecreditreport.com/pm/default.aspx?sc=668072&hmpgID=62&bcd=febemailfooterNO6 2) **************A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/100126575x1219671244x1201345076/aol?redir=http:%2F%2Fwww.freecreditreport.com%2Fpm%2Fdefault.aspx%3Fsc%3D668072%26hmpgID %3D62%26bcd%3DfebemailfooterNO62) -------------------------------1236870527 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
Randy,
 
Oh, I forgot.  I also replaced the Vernatherm, but I don't remembe= r=20 technical details of the testing (a long story involving a flash fire - best= =20 told in a bar).  I believe the chamber that the Vernatherm operate= s in=20 is such that, when cold, allows oil to bypass being sent to the cooler. = ;=20 When hot, the extension of the device shuts the bypass opening.  Thus,=20= if=20 the Vernatherm does not fully extend when hot, the bypass is not sealed and=20 uncooled oil would be returned to the system.
 
Here is one example of test results:  http= ://www.vansairforce.com/community/showthread.php?t=3D32763
 
Here is some interesting info, click on tech data: http://www.rostraver= natherm.com/oil-valves.htm
 
Here is a more interesting read: http://www.sacskyranch.com/eng= 18.htm
 
Scott.
 
In a message dated 3/12/2009 9:35:08 A.M. Central Daylight Time,=20 randylsnarr@yahoo.com writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>

Scott,

I was thinking the same thing and a= m=20 making plans to "redo" my oil cooler to cowl connection and make it=20= nice=20 and smooth. That will happen after I verify the vernatherm is doing=20= what=20 is supposed to...
I pulled out the vernatherm the other day and p= ut=20 it in boiling water to see what it would do.
I admit I really do=20= not=20 understand how it works but the spring loaded end got about 1/8" lon= ger=20 when going from room temp to 212 F.
Does that mean it is=20 working?
If anyone knows if this is good or bad, please pipe=20 in...

Thanks for the feedback!
Randy Snarr
--- On Tu= e,=20 3/10/09, Sky2high@aol.com <Sky2high@aol.com> wrote:=

From:=20 Sky2high@aol.com <Sky2high@aol.com>
Subject: [LML] Re: oi= l=20 cooling
To: lml@lancaironline.net
Date: Tuesday, March 10, 2= 009,=20 8:36 PM

Randy,
 
My large sharp=20 edged NACA duct is poorly placed on the left rearward si= de=20 of cowling.  It enters a short flexible 3" smooth rubber slee= ve=20 (plumber's sleeve) and then to a plenum above the small SW oil coo= ler=20 mounted to the fire wall.  The bottom is open to the lower=20 cowl.  I climb at about 135 KIAS and see cylinders occasional= =20 reach 400 degrees on a hot day while the oil stays at 180.  I= n=20 cruise in 30-40F temps, I must at least partially close the door=20 between the NACA and the cooler.  Recently, in 10C temps, I h= ad=20 to completely close the door to keep the oil temps about 180. In t= he=20 pattern at 100 KIAS I will see the oil go 190F or even 200F on hot= =20 days because of lack of air thru the cooler. 
 
It wasn't always=20= that=20 way.
 
When I had high o= il temps,=20 I tried a special cooler air exit to assist, no=20 help..
Another was to tr= y exiting=20 thru shark gills on the side of the cowl, no help.
I temporarily att= ached a=20 scoop to force more air in the duct, no help.
 
I finally discove= red that=20 the air was backed up in the NACA duct plenum (or chamber), thus=20 cutting off air flow.  I used Micro to smoothly shape the=20 chamber, thus directing the air into its 3" outlet (no more dead=20 corners) with the results detailed above.
 
Good Luck,=
 
Scott Krueger AKA Grayhawk
Lancair N92EX I= O320=20 SB 89/96
Aurora, IL (KARR)

In a message date= d 3/9/2009=20 12:41:32 P.M. Central Daylight Time, marv@lancair.net=20 writes:
Posted for randy snarr=20 <randylsnarr@yahoo.com>:

 All,
 Thanks= for=20 the good suggestions on the oil cooler.
 I flew again to= day=20 and my oil temps are at 208 F flying in 35 f air.
 They=20= will=20 be 215 or 220 this summer.
 I will try a few solutions t= hat=20 do not need to cut the cowl. I will most
likely make a duct=20= to=20 carry the exhaust air from the oil cooler down to the
lower=20= aft=20 part of the cowl. I have also heard that the aft vertical edge o= f=20
the naca opening should be shaped like an air foil. Mine is=20= flat=20 and fairly
sharp. The easiest way to test will to be constru= ct a=20 piece to give it a
little airfoil made from balsa or foam ta= ped=20 in place and flight tested. If
that does not work, I will ma= ke a=20 duct from the cooler to the low pressure
area on the bottom=20= of=20 the cowl and lastly would be a small lip on the bottom
of th= e=20 cowl aft.
 every producton airplane I have seen with an=20 opening on the bottom of the
cowl has 45 deg lip to create a= low=20 pressure area. I should have done that
before I=20 painted....
 
 
 I will post my findings= =20 when I get them.
 
 Randy=20 Snarr
 N694RS
 

=
--

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

A Good Credit Score is 700 or Above. See yours in just 2 easy=20 steps!
=

A Good Credit Score i= s 700 or Above. See yours in j= ust 2 easy steps!
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