X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-px0-f180.google.com ([209.85.212.180] verified) by logan.com (CommuniGate Pro SMTP 5.3.9) with ESMTP id 4473824 for flyrotary@lancaironline.net; Mon, 20 Sep 2010 14:17:37 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.212.180; envelope-from=msteitle@gmail.com Received: by pxi7 with SMTP id 7so6760662pxi.25 for ; Mon, 20 Sep 2010 11:17:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=zXnXRkD5Bpn6qspeepYWYRImsG9DNd9ZnNVyLfSDoZo=; b=tVkiU/6dY2YwDIBYv25GMjH6DYymHDrv2uxAcGBpUG5evUdTnpZC7Atguxzri47v4C 3fnIqY5p5J8PqZYItsSvMhs2cFE6n/qRFsP1Pd7H09D4kjDSeAmpGgTLYquNAnzWW+gq RLh4f5M4TexKelCw+4+AOrS/D1wLdYCH/goRs= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=W+XA7L2kVmy5hCSNtcGrxHAJL8KkdxyXUVvLcD/iWtmdfhkhoMCrIkWQ3soHEn5OTl 2hkUGYY8UHGro7b6ZbmcSX08oAelmbn6YUwhqe9dudxbWOPxNPkJ/m+6GV3GAKr427NK pVFTgxHDVVxVsub1/vJCy2kQlLafaJIFobMv8= MIME-Version: 1.0 Received: by 10.142.199.13 with SMTP id w13mr5993609wff.183.1285006622021; Mon, 20 Sep 2010 11:17:02 -0700 (PDT) Received: by 10.231.173.137 with HTTP; Mon, 20 Sep 2010 11:17:01 -0700 (PDT) In-Reply-To: References: Date: Mon, 20 Sep 2010 13:17:01 -0500 Message-ID: Subject: Re: [FlyRotary] Re: Watch that psru oil seal From: Mark Steitle To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=000e0cd254bc3d58e10490b4ebe0 --000e0cd254bc3d58e10490b4ebe0 Content-Type: text/plain; charset=ISO-8859-1 Tracy, Yes, you are correct, there is not anywhere near 80-90 lbs pressure on the back of the seal. As Lynn pointed out, the stock crancase vent line is too small. If not enlarged there could be a build up of a few pounds of pressure during high power operation. My only crankcase vent is the stock 1/4" tube located next to the oil fill hole. Since the failure occurred shortly after takeoff, when at WOT and 6800 rpm, then he is probably correct in identifying the cause. In addition to mechanically securing the seal in place, I will be adding a second, larger vent line before I fly again. Mark On Mon, Sep 20, 2010 at 12:23 PM, Tracy wrote: > Hi Mark, > Glad you got back down OK. > > Just one comment. There should not be 90 - 100 PSI trying to push the seal > out. The oil pressure drops through the passage in the input shaft and is > dissapated by the oil flowing out through the thrust bearing stack. There > should be very little pressure on the seal. > > Tracy (in Colorado) > > On Sun, Sep 19, 2010 at 3:40 AM, Mark Steitle wrote: > >> Kelly, >> >> My custom adapter plate was built on a Bridgeport mill. The hole spacing >> (and sizes) were obtained from a drawing for the actual RD-2C plate. Could >> it be a thou or two oversize? I guess that's possible, but I don't think >> so. The machinist that did the work is very meticulous. However, before >> reassembly, I'll definitely check it to be sure. The bottom line is that >> there is 90-100 psi trying to push it out of place. So, I feel that a >> mechanical fastener is the only real way to guarantee that it stays put 100% >> of the time. >> >> Mark >> >> On Sun, Sep 19, 2010 at 12:28 AM, Kelly Troyer wrote: >> >>> Mark, >>> Do you think your custom adapter plate counter-bore may be slightly >>> large in ID >>> which could have allowed the seal to work loose ??..............Just a >>> thought as my >>> adapter plate is custom (not from Tracy) to adapt my RD1C to a Mazda >>> automatic >>> transmission bell housing much like Bulent's "Cosy" Cosmo 13B >>> installation......... >>> I will compare the counter-bore of the plate from Tracy to my custom >>> plate and >>> also add a mechanical retainer such as you describe...............Seems >>> like cheap >>> insurance against a failure that could kill your engine in 2 minutes >>> plus potentially >>> cause an inflight fire.........Good Thinking and flying Mark >>> !!.............. >>> >>> Photo attached >>> >>> >>> Kelly Troyer >>> "Dyke Delta"_Turbo/13B ROTARY Engine(Eventually) >>> >>> "RWS"_RD1C/EC2/EM2 >>> "Mistral"_Back-plate/Oil Manifold >>> >>> >>> ------------------------------ >>> *From:* Mark Steitle >>> *To:* Rotary motors in aircraft >>> *Sent:* Sat, September 18, 2010 9:40:00 PM >>> >>> *Subject:* [FlyRotary] Watch that psru oil seal >>> >>> First, let me make it perfectly clear that I'm not going for the Ed >>> Anderson "Deadstick" plaque. Ed has earned it and as far as I'm >>> concerned he can just as well keep it. >>> >>> A little background: I'm running a N/A p-ported 20B powered Lancair ES. >>> I recently changed back to the old style CAS from the Renesis style CAS due >>> to inability to get the engine to run smoothly. This turns out to have been >>> a good decision because the engine is running much better with the old style >>> CAS. With the switch completed, I was ready for some ground running and >>> some fast taxi runs. This was accomplished on Friday, 9/17. It ran very >>> good, 100% improvement over the other (Renesis) CAS, reaching 6800 rpm >>> during the fast taxi. After doing a fast taxi, it felt good and everything >>> was in the green, so I decided to take a lap around the pattern. >>> It accelerated and climbed like you would expect from a p-port 3-rotor. As >>> I was turning downwind, I thought I saw a faint bit of smoke in the cabin. >>> I tried to detect if it was electrical in nature or oil. I thought it >>> smelled more like oil. I throttled back and watched the EM-2 for a sign of >>> what could be wrong. About 3/4 ways down the downwind leg the oil pressure >>> had dropped and was reading 53 psi. (The oil pressure normally runs around >>> 80psi.) I throttled back, announced my intentions, and headed for the >>> numbers. I was the only a/c in the pattern at the time. I had to slip it a >>> bit, but got on the ground without delay and taxied off the runway and >>> parked. The oil pressure had dropped to 14 psi bythe time I got it >>> shut down. The whole episode maybe lasted 2 minutes. >>> >>> Upon climbing out I could see that there was oil blown out of the side >>> cowl seams all down both sides of the fuse (I'm fortunate it didn't coat the >>> windscreen). Oil was dripping out the nose gear fairing and was forming a >>> puddle on the asphalt. I tried to imagine what could possibly have >>> failed... oil line, oil cooler, oil filter, etc. I towed it back to the >>> hangar and pulled the upper cowl. A quick look and it was evident that the >>> rear psru seal was the cause. It had come out of position and had rubbed on >>> the damper hub until it abraded through the rubber. This allowed oil to >>> flow out around the input shaft at the rear of the gearbox and be sprayed >>> all over the inner cowl. Yes, I'm very lucky there was no fire! >>> >>> I would like to point out that while I'm running an RD-2C gearbox, I'm >>> using a custom adapter plate which relocates the starter to the plugs side >>> of the engine. The seal is strictly a press fit into a counter-bore in the >>> 1/2" aluminum plate with no mechanical locking device. >>> >>> I have since removed the gearbox and plan to install a new seal with >>> two flathead screws which will be positioned so as to mechanically >>> retain the seal in the counterbore, preventing a recurrence. >>> >>> I post this only to make others aware of a potential failure mode >>> that they may otherwise not recognized as such. >>> >>> Mark >>> >>> -- >>> Homepage: http://www.flyrotary.com/ >>> Archive and UnSub: >>> http://mail.lancaironline.net:81/lists/flyrotary/List.html >>> >>> >> > --000e0cd254bc3d58e10490b4ebe0 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Tracy,
=A0
Yes, you are correct, there is not anywhere near 80-90 lbs pressure on= the back of the seal.=A0 As Lynn pointed out,=A0the stock=A0crancase vent = line is too small.=A0 If not enlarged there could be a build up of a=A0few = pounds of pressure=A0during high power operation.=A0 My only crankcase vent= =A0is the stock 1/4" tube located next to the=A0oil fill hole. =A0Sinc= e=A0the failure occurred=A0shortly after takeoff, when at WOT and 6800 rpm,= then he is probably correct in identifying the cause.=A0 In addition to me= chanically=A0securing the seal in place,=A0I=A0will be=A0adding a second, l= arger vent line before=A0I fly again.=A0
=A0
Mark
On Mon, Sep 20, 2010 at 12:23 PM, Tracy <tracy@rotaryaviat= ion.com> wrote:
Hi Mark,
=A0Glad you got back down OK.
=A0
Just one comment.=A0 There should not be 90 - 100 PSI trying to push t= he seal out.=A0 The oil pressure drops through the passage in the input sha= ft and is dissapated by the oil flowing out through the thrust bearing stac= k.=A0 There should be very little pressure on the seal.
=A0
Tracy (in Colorado)

On Sun, Sep 19, 2010 at 3:40 AM, Mark Steitle <msteitle@gmail.com> wrote:
Kelly,=A0=20

My custom adapter plate was built on a Bridgeport mill. =A0The hole sp= acing (and sizes) were obtained from a drawing for the actual RD-2C plate. = =A0Could it be a thou or two oversize? =A0I guess that's possible, but = I don't think so. =A0The machinist that did the work is very meticulous= . =A0However, before reassembly, I'll definitely check it to be sure. = =A0The bottom line is that there is 90-100 psi trying to push it out of pla= ce. =A0So, I feel that a mechanical fastener is the only real way to guaran= tee that it stays put 100% of the time. =A0

Mark

On Sun, Sep 19, 2010 at 12:28 AM, Kelly Troyer <<= a href=3D"mailto:keltro@att.net" target=3D"_blank">keltro@att.net> wrote:
Mark,
=A0=A0 Do you think your custom adapter plate counter-bore may be slig= htly large in ID
which could have allowed the seal to work loose ??..............Just a= thought as my
adapter plate is custom (not from Tracy) to adapt my RD1C to a=A0Mazda= automatic
transmission bell housing much like=A0Bulent's "Cosy" Co= smo 13B installation.........
=A0 =A0I will compare the counter-bore of the plate from Tracy to my c= ustom plate and
also add=A0a mechanical retainer such as you describe...............Se= ems like cheap
insurance=A0against a failure that could kill your engine in 2 minutes= plus=A0potentially
cause an inflight fire.........Good Thinking and flying Mark !!.......= .......
=A0
Photo attached
=A0

Kelly Troyer
"Dyke Delta"_Turbo/13B ROTARY Engine(Eventuall= y)

"RWS"_RD1C/EC2/EM2
"Mistral"_Back-plate/Oil Manif= old


<= br>
From: Mark Steitle <msteitle@gmail.com&= gt;
To: Rotary motors in= aircraft <flyrotary@lancaironline.net>
Sent: Sat, September 18, 20= 10 9:40:00 PM=20

Subject: [FlyRotar= y] Watch that psru oil seal

First, let me=A0make it perfectly clear that I'm not going for the= Ed Anderson "Deadstick" plaque.=A0 Ed has earned it and as far a= s I'm concerned=A0he can just as well keep it.
=A0
A=A0little background:=A0 I'm running a N/A=A0p-ported 20B powered= Lancair ES.=A0 I=A0recently changed back to the old style CAS from the=A0R= enesis style CAS due to=A0inability to get the=A0engine to=A0run smoothly.= =A0 This turns out to have been a good decision because=A0the engine is run= ning much better with the old style CAS.=A0 With the switch completed, I wa= s ready for some ground running and some fast taxi runs.=A0 This was accomp= lished on Friday, 9/17.=A0 It ran very good, 100% improvement over the othe= r (Renesis) CAS, reaching 6800 rpm during the fast taxi.=A0=A0After=A0doing= =A0a fast taxi, it felt good and everything was in the green, so I decided = to take a lap around the pattern.=A0 It=A0accelerated and climbed=A0like yo= u would expect from a p-port 3-rotor.=A0 As I was turning downwind, I thoug= ht I saw=A0a faint bit of smoke in the cabin.=A0 I=A0tried to detect if it = was electrical in nature or oil.=A0 I thought it smelled more like oil.=A0 = I throttled back and watched the EM-2 for=A0a sign of what could be wrong.= =A0 About 3/4 ways=A0down the downwind leg=A0the oil pressure had dropped a= nd was reading 53 psi.=A0 (The oil pressure=A0normally runs around 80psi.)= =A0 I throttled back, announced my intentions,=A0and headed for the numbers= .=A0=A0I was the only a/c in the pattern at the time.=A0 I=A0had to slip it= a bit, but got on the ground without delay and=A0taxied off the runway and= parked.=A0=A0The oil pressure had dropped to 14 psi=A0bythe time=A0I got i= t shut=A0down.=A0 The whole episode maybe=A0lasted 2 minutes.=A0=A0
=A0
Upon=A0climbing out I could see that there was oil blown out of the si= de cowl seams all down both sides of the fuse (I'm fortunate it didn= 9;t coat the windscreen).=A0 Oil was dripping out the=A0nose gear fairing a= nd=A0was forming a puddle on the asphalt.=A0 I tried to imagine what could = possibly have failed... oil line, oil cooler, oil filter, etc.=A0 I towed i= t back to the hangar and pulled the upper cowl.=A0=A0A quick look and=A0it = was evident that the rear psru seal was the cause.=A0 It had=A0come out of= =A0position and=A0had rubbed on the damper hub until it=A0abraded through t= he rubber.=A0 This allowed oil to flow out around the input shaft at the re= ar of the gearbox and be sprayed all over the inner cowl.=A0 Yes, I'm v= ery lucky there was no fire!=A0
=A0
I would like to point out that while I'm running an RD-2C gearbox,= =A0I'm using=A0a custom adapter plate=A0which relocates the starter to = the plugs side of the engine.=A0 The seal is strictly a press fit into a co= unter-bore in the 1/2" aluminum plate=A0with no mechanical locking dev= ice.=A0=A0
=A0
I have since removed the gearbox and=A0plan to install a new seal with= two=A0flathead screws which will=A0be positioned so as to=A0mechanically r= etain=A0the seal in the counterbore, preventing=A0a recurrence.=A0=A0
=A0
I post this=A0only to=A0make=A0others aware=A0of a potential failure m= ode that=A0they may=A0otherwise not=A0recognized as such.
=A0
Mark =A0=A0=A0=A0=A0=A0=A0=A0=A0=A0

--
Homepage: =A0http://www.flyrotary.com/
Archive and UnSub: =A0 <= a href=3D"http://mail.lancaironline.net:81/lists/flyrotary/List.html" targe= t=3D"_blank">http://mail.lancaironline.net:81/lists/flyrotary/List.html=



=
--000e0cd254bc3d58e10490b4ebe0--