X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.101] (HELO ms-smtp-02-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 952589 for flyrotary@lancaironline.net; Sun, 22 May 2005 08:18:27 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-065-188-083-049.carolina.res.rr.com [65.188.83.49]) by ms-smtp-02-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j4MCHe0W014792 for ; Sun, 22 May 2005 08:17:41 -0400 (EDT) Message-ID: <001f01c55ec8$4748a320$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Seized 13b Date: Sun, 22 May 2005 08:17:52 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001C_01C55EA6.BFDED100" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_001C_01C55EA6.BFDED100 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I certainly agree, Bill, and have said so many times - even a small = change can spell problems or if you don't really understand what a = particular subsystem is doing or how it functions, what problems it may = be susceptible to. Any leak in the suction side (for what ever reason) = and you are going to problems getting oil pressure up quickly. The = rotary can fly at least for a while with a cooked engine (coolant /pump = loss), but lost of lubrication will cause it to seize quickly like any = other mechanical device not properly lubricated. One small crack or pin = hole in the welding of an oil pickup tube is all it takes to cause a = problem. The bottom line is if your system does not show oil pressure within 1-2 = seconds (or less) after firing the engine, then I for one would = immediately find out why and fix the problem. While the rotary bearings = can apparently take quite a bit of abuse based on Lynn's experience - = every start with inadequate oil pressure is (in my opinion) one start = closer to a possible bearing failure. Additionally, there is some indication that the combination of the = positive pump pressure pulses and the high oil pressure of the pump = (which apparently can approach peaks of 156 psi- based the rating of oil = controller (not regulator) trip point) can cause oil coolers of less = than a robust design to fatigue and spring leaks. If you look at the = stock RX-7 cooler and compare it to a number of automotive oil cooler = you can immediately see that the stock cooler is heavy and robustly = built - one would presume for a good reason. There are non-rotary oil = coolers that would appear to be constructed to the same standard - = mostly build for the racers - which would probably work just fine. = However, many of the less expensive oil coolers are of a less robust = construction. I initially used one of EARLS oil coolers of considerably = less robust construction and while I flew almost 60 hours with it - I am = very glad (knowing what I now know) to have switched to the stock oil = cooler. Ed A ----- Original Message -----=20 From: WRJJRS@aol.com=20 To: Rotary motors in aircraft=20 Sent: Sunday, May 22, 2005 1:40 AM Subject: [FlyRotary] Re: Seized 13b In a message dated 5/21/2005 12:35:25 PM Pacific Standard Time, = eanderson@carolina.rr.com writes: Wait Bill, I am not certain if you are referring to MY oil system or = what I reported on from Andy on HIS oil system{:>). Ed please rest assured I didn't mean YOUR system. Rather that of the = engine that seized! Please know also that I don't mean to infer that plugs up can't be = done well. I do believe that many people don't understand the extent of = what they are taking on and when making the changeover. Bill Jepson ------=_NextPart_000_001C_01C55EA6.BFDED100 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I certainly agree, Bill,  and have said so many = times -=20 even a small change  can spell problems or if you don't really = understand=20 what a particular subsystem is doing or how it functions, what problems = it may=20 be susceptible to.  Any leak in the suction side (for what ever = reason) and=20 you are going to problems getting oil pressure up quickly.   = The=20 rotary can fly at least for a while with a cooked engine (coolant = /pump=20 loss), but lost of lubrication will cause it to seize quickly  like = any=20 other mechanical device not properly lubricated.  One small crack = or pin=20 hole in the welding of an oil pickup tube is all it takes to = cause a=20 problem.
 
The bottom line is if your system does not show oil = pressure=20 within 1-2 seconds (or less)  after firing the engine, then I for = one would=20 immediately find out why and fix the problem.  While the rotary = bearings=20 can apparently take quite a bit of abuse based on Lynn's experience - = every=20 start with inadequate oil pressure is (in my opinion) one start closer = to a=20 possible bearing failure.
 
 
Additionally, there is some indication that the = combination of=20 the positive pump pressure pulses and the high oil pressure of the pump = (which=20 apparently can approach peaks of 156 psi- based the rating of oil=20 controller (not regulator) trip point) can cause oil coolers of less = than a=20 robust design to fatigue and spring leaks.  If you look at the = stock RX-7=20 cooler and compare it to a number of automotive oil cooler you can = immediately=20 see that the stock cooler is   heavy and robustly built - one = would=20 presume for a good reason.  There are non-rotary oil coolers that = would=20 appear to be constructed to the same standard - mostly build for the = racers -=20 which would probably work just fine.  However, many of the less = expensive=20 oil coolers are of a less robust construction.  I initially = used one=20 of EARLS oil coolers of considerably less robust construction and = while I=20 flew almost 60 hours with it - I am very glad (knowing what I now = know) to=20 have switched to the stock oil cooler.
 
 
Ed A
----- Original Message -----
From:=20 WRJJRS@aol.com
Sent: Sunday, May 22, 2005 1:40 = AM
Subject: [FlyRotary] Re: Seized = 13b

In a message dated 5/21/2005 12:35:25 PM Pacific Standard Time, = eanderson@carolina.rr.com=20 writes:
Wait Bill, I am not certain if you are = referring=20 to MY oil system or what I reported on from Andy on = HIS oil system{:>).
Ed please rest assured I didn't mean YOUR  system. Rather = that of=20 the engine that seized!
Please know also that I don't mean to infer that plugs up can't = be done=20 well. I do believe that many people don't understand the extent of = what they=20 are taking on and when making the changeover.
Bill Jepson
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