X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from omta.toronto.rmgopenwave.com ([4.59.182.110] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3906459 for flyrotary@lancaironline.net; Fri, 30 Oct 2009 20:14:12 -0400 Received-SPF: pass receiver=logan.com; client-ip=4.59.182.110; envelope-from=lacombr@nbnet.nb.ca Received: from torspm02.toronto.rmgopenwave.com ([142.167.71.46]) by tormtz02.toronto.rmgopenwave.com (InterMail vM.8.00.01.00 201-2244-105-20090324) with ESMTP id <20091031001338.GEC2611.tormtz02.toronto.rmgopenwave.com@torspm02.toronto.rmgopenwave.com> for ; Fri, 30 Oct 2009 20:13:38 -0400 Received: from PCdeRita ([142.167.71.46]) by torspm02.toronto.rmgopenwave.com with SMTP id <20091031001337.GTZQ25014.torspm02.toronto.rmgopenwave.com@PCdeRita> for ; Fri, 30 Oct 2009 20:13:37 -0400 Message-ID: <92BC1CE7947A42FE8A51867A76D4DBE0@PCdeRita> From: "Rino" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Cooling report Date: Fri, 30 Oct 2009 21:13:34 -0300 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_008D_01CA59A5.D6C60CE0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6002.18005 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6002.18005 X-Opwv-CommTouchExtSvcRefID: str=0001.0A020202.4AEB8132.0095,ss=1,fgs=0 This is a multi-part message in MIME format. ------=_NextPart_000_008D_01CA59A5.D6C60CE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Thank you for the responses to this problem, I learn something new every = time. All I wanted to say with my story is that sometimes the problem is not = where you expect it to be. The Griffin cooler was installed exactly where the RX7 cooler was in the = first place. I replaced the RX7 cooler with the Griffin cooler. I had = to modify the duct to accomodate the larger cooler, otherwise the = ducting remained the same. The first try of the Griffin cooler was = without a fan. Then I tried with the fan -- no difference. Then I = built a oil/water exchanger and installed it in series with the Griffin = cooler. There was some improvement in the oil temp but not enough. = That is when I removed the Griffin cooler and fan and replaced it with = the RX7 cooler that I had in there in the first place. I kept the = oil/water exchanger in series, this time with the RX7 cooler. I agree that if air flow was the problem the exit air temp would be = high, mine was low. There is no by-pass air flow, the duct is sealed. The Griffin cooler, like the RX7 cooler is a double pass with both = in/out on one end. Now the story has changed, last landing I made (oat about 35) the oil = and water temp were about 120 deg F -- too cold for my taste. =20 I always wait for the oil to reach 140 deg F before takeoff. I do not = want to run the engine with the oil below that temp. So I am building = louvers to control the air flow to the two radiators. And that is with = the water rad plastered with duct tape and the oil rad air flow = restricted to a 12 cu. in. air exit. Rino ----- Original Message -----=20 From: Al Gietzen=20 To: Rotary motors in aircraft=20 Sent: Friday, October 30, 2009 8:13 PM Subject: [FlyRotary] Re: Cooling report=20 Rino, any comments on the Griffin oil cooler location and inlet = ducting Vs the RX7 oil cooler location and ducting? If oil flow was not the problem it must have been air flow. Jeff If there was not sufficient air flow, then the air outlet temp = would be very high, not very low - unless the temp number is not = correct, or there was a great deal of by-pass flow. Re: Here is my fan installation. It is a 4-blade, pull, high = flow, Spall. The inlet scoop is sealed to the other side of the rad. I = don't know whether it spins in flight when turned off, but there is no = evidence that it does. It works fine after 160 hours in flight. If it is = a concern, one could always use a relay that shorts the leads when = turned off serve as electromagnetic brake. A spinning fan would be more = restrictive to flow being forced through it than one that is stationary = - contrary to one's intuition. Al ------=_NextPart_000_008D_01CA59A5.D6C60CE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Thank you for the responses to this = problem, I=20 learn something new every time.
 
All I wanted to say with my = story is that=20 sometimes the problem is not where you expect it to be.
The Griffin cooler was installed = exactly where the=20 RX7 cooler was in the first place.  I replaced the RX7 cooler with = the=20 Griffin cooler.  I had to modify the duct to accomodate the larger = cooler,=20 otherwise the ducting remained the same.   The first try of = the=20 Griffin cooler was without a fan.  Then I tried with the fan -- no=20 difference.  Then I built a oil/water exchanger and installed it in = series=20 with the Griffin cooler.   There was some improvement in the = oil temp=20 but not enough.  That is when I removed the Griffin cooler and fan = and=20 replaced it with the RX7 cooler that I had in there in the first=20 place.  I kept the oil/water exchanger in series, this time=20 with the RX7 cooler.
 
I agree that if air flow was the = problem the exit=20 air temp would be high, mine was low.
There is no by-pass air flow, the duct = is=20 sealed.
The Griffin cooler, like the = RX7=20 cooler is a double pass with both in/out on one end.
 
Now the = story has=20 changed,  last landing I made (oat about 35) the oil and water temp = were=20 about 120 deg F  -- too cold for my taste.  =
I = always wait for the=20 oil to reach 140 deg F before takeoff.  I do not want to run the = engine=20 with the oil below that temp.  So I am building louvers to control = the air=20 flow to the two radiators.  And that is with the water rad = plastered with=20 duct tape and the oil rad air flow restricted to a 12 cu. in. air=20 exit.
 
Rino
 
 
----- Original Message -----
From:=20 Al = Gietzen=20
Sent: Friday, October 30, 2009 = 8:13=20 PM
Subject: [FlyRotary] Re: = Cooling report=20

Rino, = any=20 comments on the Griffin oil = cooler=20 location and inlet ducting Vs the RX7 oil cooler location and=20 ducting?

If oil = flow was=20 not the problem it must have been air flow.

Jeff

If = there was=20 not sufficient air flow, then the air outlet temp would be very = high, not=20 very low =96 unless the temp number is not correct, or there was a = great=20 deal of by-pass flow.

 

Re: = Here is my=20 fan installation.  It is a 4-blade, pull, high flow, Spall. =  The=20 inlet scoop is sealed to the other side of the rad.  I = don=92t know=20 whether it spins in flight when turned off, but there is no = evidence that=20 it does. It works fine after 160 hours in flight. If it is a = concern, one=20 could always use a relay that shorts the leads when turned off = serve as=20 electromagnetic brake.  A spinning fan would be more = restrictive to=20 flow being forced through it than one that is stationary =96 = contrary to=20 one=92s intuition.

 

Al

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