X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.103] (HELO ms-smtp-04-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 951250 for flyrotary@lancaironline.net; Fri, 20 May 2005 14:59:32 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; 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-04-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j4KIwhL5003982 for ; Fri, 20 May 2005 14:58:44 -0400 (EDT) Message-ID: <000901c55d6d$f6b395b0$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Case of one? [FlyRotary] Re: Sized 13b Date: Fri, 20 May 2005 14:58:51 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0006_01C55D4C.6F5A8C70" 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_0006_01C55D4C.6F5A8C70 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Well, George, appreciate all the engineering accolades you are laying on = me. However considering there have been a number of "Plugs UP" = installations in addition to mine that have never had any problem with = lubrication, I think your caution somewhat exaggerated. =20 The "bad" sump was (in my opinion) using a rubber hose on the suction = end rather than a metal tube. Any air leak at all and you lose your = ability to pull the oil up. If the hose lost stiffness due to heat, it = could partially collapse also restricting oil flow. But that apply to = the pickups in the auto orientation as well. If you have a leak (didn't = use a gasket, sealant, hole in the pickup tube, stuff stuck on your = screen, etc) on the suction side, you are going to have trouble getting = oil pressure quickly. =20 Now, I for one would consider it a problem if I couldn't get oil = pressure within 1-2 seconds of firing up the engine (regardless of = orientation) , I would cringe thinking of metal on metal rubbing, = heating, eroding, etc. I couldn't stand it and would have to fix it. =20 But, I try to avoid over generalization based on a case of one instance. = It would be like me saying that because I had apex seal failure and = was using a "Used" rotor that everyone should refrain from using = "pre-owned" rotors. Its like most other things in his "hobby", if you = don't pay attention to the details and look at the possible failure = modes, it may bite you. We now know to pay more attention to the = condition of the apex seal slot than we perhaps did before. Fuel, = cooling, ignition, etc are all equally critical (and some would say more = complex than lubrication - equally critical). So thinking about and = understanding your installation is the most time productive thing you = can probably do. However, George, There is a very valid reason I can think of not to go = "Plugs Up" All the vendors (motor mounts, PSRUs, exhausts, intakes, etc) are = building their products for the Automobile orientation (which is the = most common orientation). So if you want a compatibility with their = products, then clearly "Plugs Up" is a drawback. I had to adapt Tracy's = PSRU mount to my particular installation - not a big problem, but = clearly one due to my "Plugs Up" orientation. There are a number of = advantages in my opinion, but not trying to sell "Plugs Up", so will = refrain from enumerating them. FWIW Ed A . =20 ----- Original Message -----=20 From: WRJJRS@aol.com=20 To: Rotary motors in aircraft=20 Sent: Friday, May 20, 2005 1:08 PM Subject: [FlyRotary] Re: Sized 13b In a message dated 5/20/2005 9:13:31 AM Pacific Standard Time, = echolakeresort@telus.net writes: He said that the engine was mounted "plugs up" with a home made dry = sump system that allowed the engine to run without oil pressure on start = up until the system primed itself. The results was that all the bearings = in the engine were "wiped out" completely (didn't size up really just = stopped).=20 Geeorges,=20 It must have been a really bad "dry sump." Since the engine seized = there as a bad problem. This is a very unusual failure mode for a = rotary, that has actually started. A typical dry sump system uses a tank = remote from the engine that would always have oil above the pressure = pump. I would also suggest that unless you are real familiar with the = engine to avoid plugs up installation. With all deference to Ed A, most = of us aren't ready to set up that plumbing. I am not claiming that it = won't work, Ed's obviously does, but you are responsible for the = configuration, rather than the original engines engineers. Some people = aren't that mechanically capable. Bill Jepson ------=_NextPart_000_0006_01C55D4C.6F5A8C70 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Well, George, appreciate all the engineering = accolades you are=20 laying on me.  However considering there have been a number of = "Plugs UP"=20 installations in addition to mine that have never had any problem with=20 lubrication, I think your caution somewhat exaggerated.  =20
 
 The "bad" sump was (in my opinion) using a = rubber hose=20 on the suction end rather than a metal tube.  Any air leak at all = and you=20 lose your ability to pull the oil up. If the hose lost = stiffness due=20 to heat, it could partially collapse also restricting oil = flow. =20  But that apply to the pickups in the auto orientation as = well.  If=20 you have a leak (didn't use a gasket, sealant, hole in the pickup = tube,=20 stuff stuck on your screen, etc) on the suction side, you are going to = have=20 trouble getting oil pressure quickly. 
 
Now, I for one would consider it a problem if I = couldn't=20  get oil pressure within 1-2 seconds  of firing up the = engine=20 (regardless of orientation) , I would cringe thinking of metal on metal = rubbing,=20 heating, eroding, etc.  I couldn't stand it and would have to fix = it. =20
 
But, I try to avoid over generalization based on a = case of one=20 instance.   It would be like me saying that because I had apex = seal=20 failure and was using a "Used" rotor that everyone should refrain from = using=20 "pre-owned" rotors.  Its like most other things in his "hobby", if = you=20 don't pay attention to the details and look at the possible failure = modes,=20 it  may bite you.  We now know to pay more attention to=20 the condition of the apex seal slot than we perhaps did = before. Fuel,=20  cooling, ignition, etc are all equally critical (and some would = say more=20 complex than lubrication - equally critical).  So thinking about = and=20 understanding your installation is the most time productive thing = you can=20 probably do.
 
However, George, There is a very valid reason =  I can=20 think of not to go "Plugs Up"
 All the vendors (motor mounts, PSRUs, = exhausts, intakes,=20 etc) are building their products for the Automobile orientation (which = is the=20 most common orientation).  So if you want a compatibility with = their=20 products, then clearly "Plugs Up" is a drawback.  I had to adapt = Tracy's=20 PSRU mount to my particular installation - not a big problem, but = clearly one=20 due to my "Plugs Up" orientation.  There are a number of advantages = in my=20 opinion, but not trying to sell "Plugs Up", so will refrain from = enumerating=20 them.
 
 
FWIW
 
Ed A
 
 .  
 
 
 
 
----- Original Message -----
From:=20 WRJJRS@aol.com
Sent: Friday, May 20, 2005 1:08 = PM
Subject: [FlyRotary] Re: Sized = 13b

In a message dated 5/20/2005 9:13:31 AM Pacific Standard Time, echolakeresort@telus.net=20 writes:
He=20 said that the engine was mounted "plugs up" with a home made dry = sump system=20 that allowed the engine to run without oil pressure on start up = until the=20 system primed itself. The results was that all the bearings in the = engine=20 were "wiped out" completely (didn't size up really just stopped).=20
Geeorges,
 It must have been a really bad "dry sump." Since the engine = seized=20 there as a bad problem. This is a very unusual failure mode for a = rotary, that=20 has actually started. A typical dry sump system uses a tank remote = from the=20 engine that would always have oil above the pressure pump. I would = also=20 suggest that unless you are real familiar with the engine to avoid = plugs up=20 installation. With all deference to Ed A, most of us aren't ready to = set up=20 that plumbing. I am not claiming that it won't work, Ed's obviously = does, but=20 you are responsible for the configuration, rather than the original = engines=20 engineers. Some people aren't that mechanically capable.
Bill Jepson
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