X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.123] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3681128 for flyrotary@lancaironline.net; Fri, 12 Jun 2009 21:28:30 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.123; envelope-from=MKPerry99@cfl.rr.com Received: from mikewp2fm7y988 ([72.188.80.223]) by cdptpa-omta01.mail.rr.com with SMTP id <20090613012754459.TKGS26718@cdptpa-omta01.mail.rr.com> for ; Sat, 13 Jun 2009 01:27:54 +0000 Message-ID: From: "Mike Perry" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Water temps Date: Fri, 12 Jun 2009 21:27:54 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_009A_01C9EBA4.A6066290" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 This is a multi-part message in MIME format. ------=_NextPart_000_009A_01C9EBA4.A6066290 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I am in the process of rebuilding my engine after my water pump seal = blew and my water temp went to 260 on the 10 minute flight back to the = airport. The water pump was replaced and coolant topped off with no = leaks on a cold engine. Started the engine and within 2 minutes temps = went over 220. Shut it down and watched coolant flow out both exhaust = pipes. The engine was originally rebuilt with the factor O rings and I plan on = using Tracy's teflon kit. When I was taking the engine apart I noticed = one of the tension bolts was barely hand tight. The others were = definitely not tight enough to meet torque specs. My question is do = these bolts stretch and need replacing? Also do you still use the = hylomar gasket sealer or is there something better? Mike Perry Long EZ N981MP=20 ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Friday, June 12, 2009 8:51 PM Subject: [FlyRotary] Re: Water temps Using stock Mazda coolant "O" rings and exceeding those temperatures = would indeed compromise the "O" rings and you end up with coolant in = your combustion chamber and/or combustion gases in your coolant galleys = - I know - as it happened to me as well as others when first sorting out = my installation back over 10 years ago. =20 However, once we found and substituted TES (Teflon Encapsulate = Silicon) coolant "O" rings with a much higher temperature rating, and = Viton seals for the oil ring seals, it became quickly apparent that a = lot of the problem with elevated temperatures had been the "O" rings and = somewhat higher temperatures could now be sustained without any = apparent damage or problems. Not to say, higher temperatures are = recommended, but many of us have found brief excursions above 200F do = not cause any detectable problems.=20 =20 =20 My normal cruise coolant and oil temps are within 5F of each other and = normally range from 160F to 185F at cruise depending on power levels and = OAT. So as a percentage of operating time, my temperature excursions = are on the order of 1.6% of my total engine operating time. On a hot = 90+ day, I will exceed 200F during climbout until I hit 120 MPH IAS - = usually a brief period of from 2-3 minutes before airflow catches up = with heat being produced. =20 =20 Numerous rotary installations now fly with red lines above what would = have been prudent if using the older stock Mazda "O" rings. I have = over 8 years on my installation with TES "O" rings, Tracy Crook over 15 = years the vast majority of it with the TES "O" rings. So until we get = some aircraft with over 2000 hours on an engine (and set of TES O = rings), we really won't know whether these brief excursions are = resulting in accumulated ill effects or not. If it takes 2000 + hour to = manifest itself - then I am not concerned. =20 There is no question that the rotary can not, for the reasons = mentioned by several, with stand the temperature ranges of most piston = engines - however, we are not quite as bound by earlier limits (at least = for limited time periods) as we once were. Thanks to sturdier seals. =20 We had 8 rotary powered aircraft at the Texas Rotary Round up and it = would be interesting to know how many have exceeded 200F and any heat = associated problems. Although most have less than 500 hours, so not a = true indication of what to expect one way or the other =20 Time changes, technology advances and improvements are found. =20 Ed =20 Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://www.dmack.net/mazda/index.html http://www.flyrotary.com/ http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.rotaryaviation.com/Rotorhead%20Truth.htm =20 -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG - www.avg.com=20 Version: 8.5.339 / Virus Database: 270.12.65/2171 - Release Date: = 06/12/09 05:55:00 ------=_NextPart_000_009A_01C9EBA4.A6066290 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I am in the process of rebuilding my = engine after=20 my water pump seal blew and my water temp went to 260 on the 10 = minute=20 flight back to the airport.  The water pump was replaced and = coolant=20 topped off with no leaks on a cold engine.  Started the engine = and=20 within 2 minutes temps went over 220.  Shut it down and watched = coolant=20 flow out both exhaust pipes.
 
The engine was originally rebuilt with = the factor O=20 rings and I plan on using Tracy's teflon kit.  When I was = taking the=20 engine apart I noticed one of the tension bolts was barely hand = tight.  The=20 others were definitely not tight enough to meet torque specs.  My = question=20 is do these bolts stretch and need replacing?  Also do you still = use the=20 hylomar gasket sealer or is there something better?
 
Mike Perry
Long EZ
N981MP 
----- Original Message -----
From:=20 Ed=20 Anderson
Sent: Friday, June 12, 2009 = 8:51 PM
Subject: [FlyRotary] Re: Water=20 temps

Using stock = Mazda=20 coolant =93O=94 rings and exceeding those temperatures would indeed = compromise the=20 =93O=94 rings and you end up with coolant in your combustion chamber = and/or=20 combustion gases in your coolant galleys =96 I know - as it happened = to me as=20 well as others when first sorting out  my installation back over = 10 years=20 ago.

 

However, = once we=20 found and  substituted TES (Teflon Encapsulate Silicon) coolant =  =93O=94=20 rings with a much higher temperature rating, and Viton seals for the = oil ring=20 seals,  it became quickly apparent that a lot of the problem with = elevated temperatures had been the =93O=94 rings and somewhat =  higher=20 temperatures could now be sustained without any apparent damage or=20 problems.  Not to say, higher temperatures are recommended, but = many of=20 us have found brief excursions above 200F do not cause any detectable=20 problems.

 

 

My normal = cruise=20 coolant and oil temps are within 5F of each other and normally range = from 160F=20 to 185F at cruise depending on power levels and OAT.  So as a = percentage=20 of operating time, my temperature excursions are on the order of 1.6% = of my=20 total engine operating time.  On a hot 90+ day, I will exceed = 200F during=20 climbout until I hit 120 MPH IAS =96 usually a brief period of from = 2-3 minutes=20 before airflow catches up with heat being produced. =20

 

Numerous = rotary=20 installations now fly with red lines above what would have been =  prudent=20 if using the older stock Mazda =93O=94 rings.  I have over 8 = years on my=20 installation with TES =93O=94 rings, Tracy Crook over 15 years the = vast majority=20 of it with the TES  =93O=94 rings.  So until we get some = aircraft with=20 over 2000 hours on an engine (and set of TES O rings), we really = won=92t know=20 whether these brief excursions are resulting in accumulated ill = effects or=20 not.  If it takes 2000 + hour to manifest itself =96 then I am = not=20 concerned.

 

There is no = question=20 that the rotary can not, for the reasons mentioned by several, with = stand the=20 temperature ranges of most piston engines =96 however, we are not = quite as bound=20 by earlier limits (at least for limited time periods) as we once = were. =20 Thanks to sturdier seals.

 

We had 8 = rotary=20 powered aircraft at the Texas Rotary Round up and it would be = interesting to=20 know how many have exceeded 200F and any heat associated = problems. =20 Although most have less than 500 hours, so not a true indication of = what to=20 expect one way or the other

 

Time = changes,=20 technology advances and improvements are = found.

 

Ed

 

Ed=20 Anderson

Rv-6A = N494BW Rotary=20 Powered

Matthews,=20 NC

eanderson@carolina.rr.com

http://www.andersonee.com

http://www.dmack.net/mazda/index.html

http://www.flyrotary.com/

http://members.cox.net/rogersda/rotary/configs.htm#N494BW

http://www.r= otaryaviation.com/Rotorhead%20Truth.htm

 


No virus found in this incoming message.
Checked by AVG = -=20 www.avg.com
Version: 8.5.339 / Virus Database: 270.12.65/2171 - = Release=20 Date: 06/12/09 05:55:00
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