Return-Path: Received: from [65.54.168.107] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 3068572 for flyrotary@lancaironline.net; Mon, 08 Mar 2004 01:40:42 -0500 Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 7 Mar 2004 22:40:42 -0800 Received: from 67.24.247.63 by bay3-dav3.bay3.hotmail.com with DAV; Mon, 08 Mar 2004 06:40:41 +0000 X-Originating-IP: [67.24.247.63] X-Originating-Email: [lors01@msn.com] X-Sender: lors01@msn.com From: "Tracy Crook" To: "Rotary motors in aircraft" Subject: Re: [FlyRotary] Re: Ideal Cooling System Plumbing(wasRe:[FlyRotary]Re:overflow Date: Mon, 8 Mar 2004 01:40:39 -0500 MIME-Version: 1.0 X-Mailer: MSN Explorer 7.02.0011.2700 Content-Type: multipart/alternative; boundary="----=_NextPart_001_0001_01C404AE.5CB93A00" Message-ID: X-OriginalArrivalTime: 08 Mar 2004 06:40:42.0043 (UTC) FILETIME=[46CBE0B0:01C404D8] ------=_NextPart_001_0001_01C404AE.5CB93A00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable OK David, I see what you mean. This could give an indication of trouble = in some circumstances. Although you would need to fully characterize the= system. Changing the pressurized reservoir size, coolant level when fil= led, temperature when filled, etc, would all affect the results. Tracy ----- Original Message ----- From: David Carter Sent: Sunday, March 07, 2004 4:31 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Ideal Cooling System Plumbing(wasRe:[FlyRotary]R= e:overflow I have a feeling that we are talking about two different "coolant level sensors". The one I'm talking about is in the "pressurized coolant/expansion/header tank" like a late 90's Ford Taurus. The point t= hat must be noted to discuss this "logically" is that the coolant level in th= is tank ("FULL - HOT") is ABOVE the top of the high spot for coolant in the engine. And, there is air space above the FULL- HOT level. There is not other expansion tank. Coolant doesn't go "somewhere else". That is as high as the level gets (unless there is blowby which is discussed last below.) But, to discuss LEAKS, not BLOWBY/STEAM: This being the case, if the coolant level in this tank goes down and the "low" sensor activates, there is still coolant in the engine block (unles= s the coolant tank is very deep, where bottom is WAY below the top of engin= e - not the case on the Ford). If this is so, then how could the "coolant lo= w" light NOT be a good indicator that you have a leak? - None of the coolant is being "expanded" into an unpressurized "expansion tank". That unpressurized tank is REPLACED by this "pressuriz= ed coolant/expansion/header tank". Coolant does not "expand" "OUT" of this tank. It is THE expansion tank. - I think we are mixing the two systems in this discussion. This "pressurized coolant/exp/hdr tank" is part of the CLOSED system - it is n= ot "external" to the cooling system. It is PART OF THE SYSTEM - and if its level goes down, then the entire closed system is losing coolant - the SYSTEM has a leak. - When the sensor in this tank turns on the "low" or "check coolant= " light, then you have a leak - and you know it immediately upon losing ab= out 1/2 or 1 qt (whatever is in this tank between "Full - Hot" and the "low sensor". Yes we should know the pressure indications of problems - but I don't thi= nk we have anyone flying with a tank with a fluid level indication system. Thus, there will be no "real stories" to validate this proposed Ideal Cooling System. (ref someone else's post asking for "proof"). And, yes, if there is blowby as mentioned earlier (compression/combustion gasses leaking by bad seals into the cooling passages and forcing HIGH pressure into the coolant galleys) then, because this high pressure is greater than the cap's release pressure, this blowby WILL force liquid pa= st the cap and out wherever you have it plumbed to go. - I would simply route the rubber line from that "cap pressure relea= se overflow fitting" to go up and spray up beside the windscreen where I cou= ld see it - to warn me that I was either suffering compression blowby - eith= er from bad seals or from overheating and steaming. In either case, I'd hav= e instant warning that I need to terminate the flight ASAP. - It would be an desireable increase in parts count and would MASK t= he problem to vent the "pressure cap blowby" into some other "expansion tank= " that you couldn't see or might not immediately notice. In summary, in the absence of "high pressure above cap release pressure" = in this CLOSED system, a fluid level indicator system should give you an ear= ly, positive, and adequate warning that you have a leak, whether you notice t= he pressure "clues" or not. David ----- Original Message ----- =20 From: "Tracy Crook" To: "Rotary motors in aircraft" Sent: Sunday, March 07, 2004 10:33 AM Subject: [FlyRotary] Re: Ideal Cooling System Plumbing (wasRe:[FlyRotary]Re:overflow > FIRST the pressure drops precipitously, and THEN the coolant level > starts to go down ... FINALLY the temps start to rise (provided the > temp sender is submerged in what water remains). Just a brief comment on this part. Coolant level sensors are of almost n= o use in this application. It is commonly assumed that the temp gauge read= s low as soon as the sensor is no longer submerged. Not true. It only dro= ps after the coolant is all boiled away because steam will heat the sensor. = If you haven't caught the problem long before this, it's too late anyway. Tracy >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_001_0001_01C404AE.5CB93A00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
OK David, I se= e what you mean.  This could give an indication of trouble in some c= ircumstances.  Although you would need to fully characterize the sys= tem.  Changing the pressurized reservoir size, coolant level when fi= lled, temperature when filled, etc, would all affect the results.
<= DIV> 
Tracy
 
-----= Original Message -----
From: David Carter
Sent: Sunday, March 07, 2004 4:31 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Ideal Cooling S= ystem Plumbing(wasRe:[FlyRotary]Re:overflow
 
I have= a feeling that we are talking about two different "coolant level
sens= ors".  The one I'm talking about is in the "pressurized
coolant/e= xpansion/header tank" like a late 90's Ford Taurus.  The point that<= BR>must be noted to discuss this "logically" is that the coolant level in= this
tank ("FULL - HOT") is ABOVE the top of the high spot for coolan= t in the
engine.  And, there is air space above the FULL- HOT lev= el.  There is not
other expansion tank.   Coolant doesn= 't go "somewhere else".  That is as
high as the level gets (unles= s there is blowby which is discussed last
below.)  But, to discus= s LEAKS, not BLOWBY/STEAM:

This being the case, if the coolant lev= el in this tank goes down and  the
"low" sensor activates, there = is still coolant in the engine block (unless
the coolant tank is very = deep, where bottom is WAY below the top of engine -
not the case on th= e Ford).  If this is so, then how could the "coolant low"
light N= OT be a good indicator that you have a leak?
    - = ; None of the coolant is being "expanded" into an unpressurized
"expan= sion tank".  That unpressurized tank is REPLACED by this "pressurize= d
coolant/expansion/header tank".  Coolant does not "expand" "OUT= " of this
tank.  It is THE expansion tank.
    = - I think we are mixing the two systems in this discussion.   T= his
"pressurized coolant/exp/hdr tank" is part of the CLOSED system - = it is not
"external" to the cooling system.  It is PART OF THE SY= STEM - and if its
level goes down, then the entire closed system is lo= sing coolant - the
SYSTEM has a leak.
    - &nb= sp; When the sensor in this tank turns on the "low" or "check coolant"light, then you have a leak - and you know it immediately upon losing&nb= sp; about
1/2 or 1 qt (whatever is in this tank between "Full - Hot" a= nd the "low
sensor".

Yes we should know the pressure indication= s of problems - but I don't think
we have anyone flying with a tank wi= th a fluid level indication system.
Thus, there will be no "real stori= es" to validate this proposed Ideal
Cooling System. (ref someone else'= s post asking for "proof").

And, yes, if there is blowby as mentio= ned earlier (compression/combustion
gasses leaking by bad seals into t= he cooling passages and forcing HIGH
pressure into the coolant galleys= ) then, because this high pressure is
greater than the cap's release p= ressure, this blowby WILL force liquid past
the cap and out wherever y= ou have it plumbed to go.
    -  I would simply ro= ute the rubber line from that "cap pressure release
overflow fitting" = to go up and spray up beside the windscreen where I could
see it - to = warn me that I was either suffering compression blowby - either
from b= ad seals or from overheating and steaming.  In either case, I'd have=
instant warning that I need to terminate the flight ASAP.
 &n= bsp;  -  It would be an desireable increase in parts count and = would MASK the
problem to vent the "pressure cap blowby" into some oth= er "expansion tank"
that you couldn't see or might not immediately not= ice.

In summary, in the absence of "high pressure above cap releas= e pressure" in
this CLOSED system, a fluid level indicator system shou= ld give you an early,
positive, and adequate warning that you have a l= eak, whether you notice the
pressure "clues" or not.

David
<= BR>----- Original Message -----
From: "Tracy Crook" <lors01@msn.co= m>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net&= gt;
Sent: Sunday, March 07, 2004 10:33 AM
Subject: [FlyRotary] Re: = Ideal Cooling System Plumbing
(wasRe:[FlyRotary]Re:overflow

>   FIRST the pressure drops precipitously, and THEN the co= olant level
> starts to go down ... FINALLY the temps start to rise= (provided the
> temp sender is submerged in what water remains).

Just a brief comment on this part.  Coolant level sensors = are of almost no
use in this application.  It is commonly assumed= that the temp gauge reads
low as soon as the sensor is no longer subm= erged.  Not true.  It only drops
after the coolant is all bo= iled away because steam will heat the sensor.  If
you haven't cau= ght the problem long before this, it's too late anyway.

Tracy
<= BR>

>>  Homepage:  http://www.flyrotary.com/
&g= t;>  Archive:   http://lancaironline.net/lists/flyrotar= y/List.html
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