X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imf21aec.mail.bellsouth.net ([205.152.59.69] verified) by logan.com (CommuniGate Pro SMTP 4.3.5) with ESMTP id 1021772 for flyrotary@lancaironline.net; Sat, 25 Jun 2005 22:46:39 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.69; envelope-from=sladerj@bellsouth.net Received: from ibm63aec.bellsouth.net ([65.8.219.22]) by imf21aec.mail.bellsouth.net with ESMTP id <20050626024549.LXFK2460.imf21aec.mail.bellsouth.net@ibm63aec.bellsouth.net> for ; Sat, 25 Jun 2005 22:45:49 -0400 Received: from JSLADE ([65.8.219.22]) by ibm63aec.bellsouth.net with ESMTP id <20050626024549.BRHW25209.ibm63aec.bellsouth.net@JSLADE> for ; Sat, 25 Jun 2005 22:45:49 -0400 From: "John Slade" To: "Rotary motors in aircraft" Subject: RE: [FlyRotary] Re: Coolant Leak Date: Sat, 25 Jun 2005 22:45:46 -0400 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_020B_01C579D7.A04A2370" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 Importance: Normal This is a multi-part message in MIME format. ------=_NextPart_000_020B_01C579D7.A04A2370 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit OK, Dave. If that makes sense, explain this.... :) After start-up - 29 psi (24 psi cap) Run-up 25 PSI Two trips around the pattern - zero PSI the entire time third downwind - 8 PSI. taxi back to hangar - 10 PSI. After cool down - coolant still full to the brim. I'd blame the instrument if I didnt have two of them. and no, I don't have a thermostat. John On 6/24/05, Ed Anderson wrote: Al, all I can tell you is that the pressure would go immediately (within 2 seconds) to 21-24 psi. Then as the engine warmed up the pressure would drop to a nominal 8 psi or so. It seem likely that the pressure sensor was responding to small variations in the coolant volume. But, certainly open to another explanation. It was not coolant/combustion chamber leaks of that much I am certain. Tracy found the same thing, have not heard any other similar reports until John Slade mention his coolant pressure build up. Ed It makes sense to me Ed. Heat the coolant just a little, and it needs to expand just a little. In order for any of the coolant to flow out past the cap (even just a little coolant), it must reach the pressure rating of the cap. Once the engine is warm, there is no longer any need for the coolant to leave so it does not reach the full rated pressure of the cap. -- Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/vp4skydoc/index.html ------=_NextPart_000_020B_01C579D7.A04A2370 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
OK,=20 Dave. If that makes sense, explain this.... :)
    After start-up - 29 psi = (24 psi=20 cap)
    Run-up  25=20 PSI
    Two trips around the = pattern - zero=20 PSI the entire time
    third downwind - 8=20 PSI.
    taxi back to hangar - 10=20 PSI.
    After cool down - coolant = still full=20 to the brim.
I'd=20 blame the instrument if I didnt have two of them.
and=20 no, I don't have a thermostat.
John
 

On 6/24/05, Ed=20 Anderson <eanderson@carolina.rr.com&g= t;=20 wrote:=20
 Al, all I can tell you is that the = pressure=20 would go immediately (within   2 seconds) to 21-24 = psi.  Then=20 as the engine warmed up the pressure would drop to a nominal 8 psi = or=20 so.  It seem likely that the pressure sensor was responding to = small=20 variations in the coolant volume.  But, certainly open to = another=20 explanation.  It was not coolant/combustion chamber leaks of = that much=20 I am certain.  Tracy found the same thing, have not heard any = other=20 similar reports until John Slade mention his coolant pressure = build up.=20
 
Ed
 
It makes sense to me Ed.  Heat the coolant just a little, = and it=20 needs to expand just a little.  In order for any of the coolant = to flow=20 out past the cap (even just a little coolant), it must reach the = pressure=20 rating of the cap.
 
Once the engine is warm, there is no longer any need for the = coolant to=20 leave so it does not reach the full rated pressure of the cap.
--
Dave Leonard
Turbo Rotary RV-6 N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html
http://members.aol.c= om/vp4skydoc/index.html=20
------=_NextPart_000_020B_01C579D7.A04A2370--