X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from rn-out-0910.google.com ([64.233.170.187] verified) by logan.com (CommuniGate Pro SMTP 5.2c4) with ESMTP id 2699828 for flyrotary@lancaironline.net; Wed, 30 Jan 2008 10:50:51 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.233.170.187; envelope-from=msteitle@gmail.com Received: by rn-out-0910.google.com with SMTP id e13so37261rng.4 for ; Wed, 30 Jan 2008 07:50:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references; bh=meesCJ7PaOuG5JWo0RY44neoJMENcFlITQsq+FXB0wQ=; b=JFtYtLsrucMYI0o16QsBlQ1pTubfyLpJln5gT1upydusqUX8CuZ5aSdPEBhR0emf83KGn1EIDeyQab7KDZh6rcnNM0ih/KgaMqbJSd6pembbKSJvDzOAn7jSaZ2hpRFNAyhHlf+SD2SGuK6Nq7MNizl0GNJv0sJ5MBpOnrnIfFw= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references; b=FCfgG82XRMMMMQXjQOMMw1e2vl1owHzUJHai1kdjeCXwfZMYpsItDwBGXENiu8PdkzyV+2IJVqFWZdzaJ6jQsm2jOwFFp1svM6cGqp0O43sYm/+KqfQdic5CN5pvBCvPOpFS/4IfNpGLH0kAQDn/eW+6trfCvGuxx/dVLBfmJH0= Received: by 10.142.88.20 with SMTP id l20mr411838wfb.72.1201708210714; Wed, 30 Jan 2008 07:50:10 -0800 (PST) Received: by 10.70.20.3 with HTTP; Wed, 30 Jan 2008 07:50:10 -0800 (PST) Message-ID: <5cf132c0801300750w41d5d908he24ba6913f6e965f@mail.gmail.com> Date: Wed, 30 Jan 2008 09:50:10 -0600 From: "Mark Steitle" To: "Rotary motors in aircraft" Subject: Re: [FlyRotary] Re: Emailing: damage24.jpg In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_5238_3404668.1201708210655" References: ------=_Part_5238_3404668.1201708210655 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline Ed, Murphy never sleeps. Mark (how well I know) On 1/30/08, Ed Anderson wrote: > > I agree, Bill. > > While the example shown was not an aircraft rotor, I did indeed loose > the triangular bit of the apex seal during reassemble. It fell between > rotor and side housing into one of those lightening/balancing divots cut > into the rotor - Just my luck. If it had not fallen into the divot but had > simply got between the rotor and side housing, I doubt seriously that the > engine would have turned over at all. As, it was, it did turn over, yes, > with resistance - because I was in a hurry to get my aircraft back from the > unattended airport, I convinced my self the "resistance" was just sign of a > "good rebuild" with good solid compression. > > Here are a few things that I should have paid attention to: > > 1. It took a bit of effort to hand turn the flywheel > 2. While cranking it, was turning over slower than normal > 3. When I fired it up it would not idle below 2000 rpm (obviously due to > the high resistance) > 4. After the first hour of running everything was "normal" in that it > would now idle at lower rpm and the resistance was "gone" > > Of course by step 4 the hour of running apparently wore the seal piece > down and the rotor housing had already incurred the damage that the friction > caused - which later led to my rebuild while stuck in Louisiana for 4 weeks. > > Clearly having a dial torque reading to compare would have helped. In > fact, Bruce Turrentine and several folks told me something was not right - > and I should have listened, but just in too much of hurry to get it done and > into the aircraft - so I got to do it again, correct this time {:>) > > So your suggestion certainly has merit. > > Ed > > > > ----- Original Message ----- > *From:* WRJJRS@aol.com > *To:* Rotary motors in aircraft > *Sent:* Wednesday, January 30, 2008 1:04 AM > *Subject:* [FlyRotary] Re: Emailing: damage24.jpg > > > Ed and group, > This assembly problem is vexing. We really need to avoid these types of > foul up! When I built race cars and motorcycles the assembler (usually me) > would try to learn what kind of force it should require to turn over a newly > built engine. That is, how much friction to expect when turning over a brand > spanking new engine for the first time. Cosworth even has a torque table > that suggests you use a dial torque wrench for that first rev or two. If you > see higher than suspected torque do not turn the engine over or even through > the tight spot! Learning these forces saved one of my best customers a > completely mangled engine! (Anecdote warning!) > Guy M. my customer informed me that he would do the basic assembly of the > "long block" including putting on the head so all I would have to do was > time the cams. (Engine was a Kawasaki 900 with considerable modification to > run in an SCCA C sports racer.) Guy was an EXCELLENT mechanic in his own > right so I thought, "great that part is easy but tedious so I won't have to > do it." I installed the cams correctly, and did the all important first > revolution by hand. At TDC there was a very small change in friction, that > would have been easy to miss if I had not been super familiar with that > engine. Guy wanted to just run it, but I wouldn't do it because that is > where the engine has nearly no piston movement for about 20 degrees. I made > him pull the head and was super glad I did. Guy had installed all four > pistons reversed on the piston pin. The large valve cut out was on the > exhaust valve side rather than the intake as was normal. The "tick" was the > intake valve rubbing on the side of the piston cutout! If we had started the > engine it would have run for a few seconds until the intake valves bent! We > corrected the problem, and thankfully the intakes were not even bent. > Believe me we checked. The result was a few hours lost rather than a > destroyed engine. > We need to develop a data base here. So if you do a new build up, or any > build up for that matter, do us all a favor and put a dial torque wrench on > there and record your max turn over torque. Oh yea, do that with the plugs > out of course. On a rotary with plugs out you should get a pretty even > torque with no compression so if you get any spikes in there you may want to > pull it apart again before you do some serious damage. Mistakes can happen > even to very competent mechanics so it would be a great help to everybody > and might even save you some cash. Just a good idea. My $0.02. > Bill Jepson > > In a message dated 1/29/2008 7:32:20 AM Pacific Standard Time, > eanderson@carolina.rr.com writes: > > I agree, Bob, there is no way that apex seal could come out of its recess > without that part of the rotor being broken off. Those small parts can be > illusive, particularly when you turn the rotor upside down to place it on > the e shaft - make certain you use good Vaseline or halomire stickum {:>). > > Ed > > > > > > ------------------------------ > Start the year off right. Easy ways to stay in shapein the new year. > > ------=_Part_5238_3404668.1201708210655 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
Ed,
 
Murphy never sleeps.
 
Mark
(how well I know)
 
On 1/30/08, = Ed Anderson <eanderson@= carolina.rr.com> wrote:
I agree, Bill.
 
  While the example shown was not an aircraft ro= tor, I did indeed loose the triangular bit of the apex seal during reassemb= le.  It fell between rotor and side housing into one of those lighteni= ng/balancing divots cut into the rotor - Just my luck.  If it had not = fallen into the divot but had simply got between the rotor and side housing= , I doubt seriously that the engine would have turned over at all.  As= , it was, it did turn over, yes, with resistance - because I was in a hurry= to get my aircraft back from the unattended airport, I convinced my self t= he "resistance" was just sign of a "good rebuild" with = good solid compression. 
 
Here are a few things that I should have paid attenti= on to:
 
1.  It took a bit of effort to hand turn the fly= wheel
2.  While cranking it, was turning over slower t= han normal
3.  When I fired it up it would not idle below 2= 000 rpm (obviously due to the high resistance)
4.  After the first hour of running everything w= as "normal" in that it would now idle at lower rpm and the resist= ance was "gone"
 
Of course by step 4 the hour of running apparently wo= re the seal piece down and the rotor housing had already incurred the damag= e that the friction caused - which later led to my rebuild while stuck in L= ouisiana for 4 weeks.
 
Clearly having a dial torque reading to compare would= have helped.  In fact, Bruce Turrentine and several folks told me som= ething was not right - and I should have listened, but just in too much of = hurry to get it done and into the aircraft - so I got to do it again, corre= ct this time {:>)
 
So your suggestion certainly has merit.
 
Ed
 
 
----- Original Message -----
From: WRJJRS@aol.com
Sent: Wednesday, January 30, 2008 1:= 04 AM
Subject: [FlyRotary] Re: Emailing: d= amage24.jpg

 
Ed and group,
This assembly problem is vexing. We really need to avoid these types o= f foul up! When I built race cars and motorcycles the assembler (usually me= ) would try to learn what kind of force it should require to turn over a ne= wly built engine. That is, how much friction to expect when turning over a = brand spanking new engine for the first time. Cosworth even has a torque ta= ble that suggests you use a dial torque wrench for that first rev or two. I= f you see higher than suspected torque do not turn the engine over or even = through the tight spot! Learning these forces saved one of my best customer= s a completely mangled engine! (Anecdote warning!)
 Guy M. my customer informed me that he would do the ba= sic assembly of the "long block" including putting on the he= ad so all I would have to do was time the cams. (Engine was a Kawasaki = ;900 with considerable modification to run in an SCCA C sports racer.)=  Guy was an EXCELLENT mechanic in his own right so I thought, "gr= eat that part is easy but tedious so I won't have to do it." = I installed the cams correctly, and did the all important first revolution = by hand. At TDC there was a very small change in friction, that would have = been easy to miss if I had not been super familiar with that engine. Guy wa= nted to just run it, but I wouldn't do it because that is where the eng= ine has nearly no piston movement for about 20 degrees. I made hi= m pull the head and was super glad I did. Guy had installed all four piston= s reversed on the piston pin. The large valve cut out was on the exhau= st valve side rather than the intake as was normal. The "tick" wa= s the intake valve rubbing on the side of the piston cutout! If we had star= ted the engine it would have run for a few seconds until the intake va= lves bent! We corrected the problem, and thankfully the intakes were not ev= en bent. Believe me we checked. The result was a few hours lost rather than= a destroyed engine.
 We need to develop a data base here. So if you do a new build up= , or any build up for that matter, do us all a favor and put a dial torque = wrench on there and record your max turn over torque. Oh yea, do that = with the plugs out of course. On a rotary with plugs out you should ge= t a pretty even torque with no compression so if you get any spikes in= there you may want to pull it apart again before you do some serious = damage. Mistakes can happen even to very competent mechanics so it wou= ld be a great help to everybody and might even save you some cash. Jus= t a good idea. My $0.02.
Bill Jepson
 
In a message dated 1/29/2008 7:32:20 AM Pacific Standard Time, eanderson@carolina.rr.com writes:=
I agree, Bob, there is no way that apex seal coul= d come out of its recess without that part of the rotor being broken off.&n= bsp; Those small parts can be illusive, particularly when you turn the roto= r upside down to place it on the e shaft - make certain you use good Vaseli= ne or halomire stickum {:>).
 
Ed
 



Start the year off right. Easy ways to stay in shape i= n the new year.

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