X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from ms-smtp-03.southeast.rr.com ([24.25.9.102] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1110675 for flyrotary@lancaironline.net; Fri, 12 May 2006 11:56:39 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.102; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-025-165.carolina.res.rr.com [24.74.25.165]) by ms-smtp-03.southeast.rr.com (8.13.6/8.13.6) with SMTP id k4CFtqKJ008176 for ; Fri, 12 May 2006 11:55:54 -0400 (EDT) Message-ID: <001801c6744a$451e3f90$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Black vice Blue was [FlyRotary] Re: oil cooling issues Date: Wed, 10 May 2006 11:56:15 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0015_01C67428.BDBB9960" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0015_01C67428.BDBB9960 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message ----- Original Message -----=20 From: Tracy Crook=20 To: Rotary motors in aircraft=20 Sent: Friday, May 12, 2006 11:42 AM Subject: [FlyRotary] Re: oil cooling issues ----- Original Message -----=20 From: Al Gietzen=20 To: Rotary motors in aircraft=20 Sent: Friday, May 12, 2006 10:41 AM Subject: [FlyRotary] Re: oil cooling issues I have seen 260 F. many times, and I consider that normal during = climb and taxi. I also use Mobil One Synthetic oil, to tolerate the heat. During cruise it will stabilize at 220F. =20 You need to get the oil above 220 F, to evaporate the moisture = anyway.=20 Hi George, The "standard" (closest we have to one) for measuring oil temp is to = measure it as it returns to the engine, after the cooler. According to = Racing Beat, this temp should never exceed 210 F. Lot's of folks have = exceeded this for short periods, up to 240 F or so, and have had no = problems, but it's not something you really want to keep doing. =20 As I understand it, the issue is not the breakdown of the oil, but = the melting of the rotor bearings. =20 Hum-m. I was under the impression that the limiting factor side = seal O-rings. I've had the oil temp (after cooler) up to 220 -225 a few times for = very short periods on the ground. With no effective air flow through = the cooler, the before-cooler temp was only 3-4 degrees higher. It's a = different issue when running at high power where before-cooler temps may = be 30-50 degrees higher. Al That is my impression as well. Auto racing is another matter. They = are stressing the rotor bearings a lot more than we are (mainly due to = RPM) so that is probably the weak link in their use.=20 Your numbers for pre/post oil cooler temps are what I am seeing = when in-flight, I.e. 180 after the cooler =3D 220 - 230 in the pan. = This is a valuable number with which to judge oil cooler effectiveness. = If you don't get this much delta or more, your cooler is too small or = airflow too little. =20 Tracy (still can't figure out why I can't change text color after = Al's stuff) That's because Al apparently has set the font to color blue in the font = format menu, this apparently precludes you from changing it in your = reply by using the simple alphabet color selection at the head of the e = mail window. However, if=20 you go into the format/font menu and select the color palette and then = select color black and then specify color black in the font dialog box and then select "black" from the "A" box, = you can be back into the color "black". Yes, a slow day here {:>) Ed ------=_NextPart_000_0015_01C67428.BDBB9960 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
 
----- Original Message -----
From:=20 Tracy = Crook
Sent: Friday, May 12, 2006 = 11:42 AM
Subject: [FlyRotary] Re: oil = cooling=20 issues

 
----- Original Message -----
From: Al=20 Gietzen
To: Rotary motors in = aircraft=20
Sent: Friday, May 12, 2006 = 10:41=20 AM
Subject: [FlyRotary] Re: oil = cooling=20 issues

I have seen 260 F. many = times, and I=20 consider that normal during climb
and taxi.  I also use = Mobil One=20 Synthetic oil, to tolerate the heat.
During cruise it will = stabilize at=20 220F. 

You need to get the oil above 220 F, to = evaporate the=20 moisture anyway. 

 

Hi George,

 

The=20 "standard" (closest we have to one) for measuring oil temp is to = measure it=20 as it returns to the engine, after the cooler.  According to = Racing=20 Beat, this temp should never exceed 210 F.  Lot's of folks have = exceeded this for short periods, up to 240 F or so, and have had no=20 problems, but it's not something you really want to keep=20 doing.  

 

As I=20 understand it, the issue is not the breakdown of the oil, = but the=20 melting of the rotor bearings.

 =20

Hum-m.  I=20 was under the impression that the limiting factor side seal=20 O-rings.

 

I=92ve = had the oil=20 temp (after cooler) up to 220 -225 a few times for very short = periods on the=20 ground.  With no effective air flow through the cooler, the=20 before-cooler temp was only 3-4 degrees higher.  It=92s a = different issue=20 when running at high power where before-cooler temps may be 30-50 = degrees=20 higher.

 

Al

 

That is = my=20 impression as well.  Auto racing is another matter.  They = are=20 stressing the rotor bearings a lot more than we are (mainly due to = RPM) so=20 that is probably the weak link in their = use. 

 

 Your=20 numbers for pre/post oil cooler temps are what I am seeing when = in-flight,=20 I.e. 180 after the cooler =3D 220 - 230 in the pan.   This = is a=20 valuable number with which to judge oil cooler = effectiveness.   If=20 you don't get this much delta or more, your cooler is too small or = airflow=20 too little.  

 

Tracy =20 (still can't figure out why I can't change text color after Al's=20 stuff)

 
That's because Al apparently has set = the font to=20 color blue in the font format menu, this apparently precludes you from = changing=20 it in your reply by using the simple alphabet color selection at the = head of the=20 e mail window. However, if=20
you go into the format/font menu and select the color = palette and=20 then select color black and then specify color
black in the font dialog box and = then select=20 "black" from the "A" box, you can be back into the color "black".  = Yes, a=20 slow day here {:>)
 
Ed
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