X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao101.cox.net ([68.230.241.45] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3734554 for flyrotary@lancaironline.net; Sat, 27 Jun 2009 10:31:54 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.45; envelope-from=alventures@cox.net Received: from fed1rmimpo01.cox.net ([70.169.32.71]) by fed1rmmtao101.cox.net (InterMail vM.7.08.02.01 201-2186-121-102-20070209) with ESMTP id <20090627143119.BZTP17670.fed1rmmtao101.cox.net@fed1rmimpo01.cox.net> for ; Sat, 27 Jun 2009 10:31:19 -0400 Received: from BigAl ([72.192.133.78]) by fed1rmimpo01.cox.net with bizsmtp id 92XK1c0071hf1Cg032XKL6; Sat, 27 Jun 2009 10:31:19 -0400 X-VR-Score: 0.00 X-Authority-Analysis: v=1.0 c=1 a=8HhviUkxs-0A:10 a=oAZ-FXvoxA0zMC_lC1AA:9 a=JHcOWcORKE4y9C6FezIfSH0LoM4A:4 a=t68PIdcsMFdeDyKhQnUA:9 a=l5LW_30fNWwHWJtgAroA:7 a=OjszsxF1PDDlcbGUqejgyvrQRi4A:4 X-CM-Score: 0.00 From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] More progress, more questions.... Date: Sat, 27 Jun 2009 07:31:39 -0800 Message-ID: <6CD2A1966E134394B1C1C22615164E39@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0009_01C9F6F9.4F711370" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6838 Thread-Index: Acn28h8Jeu4Qo7cgSKyAmW8ERDj5sQARFGQg X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 Importance: Normal In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_0009_01C9F6F9.4F711370 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable I am concerned about some sputtering that is present around idle. It is = generally pretty smooth, but sputters too. Not sure what is causing it=20 yet. Thoughts? =20 Don't know exactly you definition of sputtering, But could be a = combination of factors, including some mixture tuning required. My engine is smooth = down to about 1500, then begins to miss the occasional beat as I slow it = further, and gets a bit rough down at 1000. It might help if you can figure out = why you have to 'pump' the throttle to make it slow down. =20 I don't have a clue about the RPM inconsistency, but on the photo of the = EM2 panel it looks like voltage is 11.1, but can't tell for sure. Did you = not have the field current on the alternator? If you tune the engine with = the voltage at about 14.0; then run at 11, it will be out of tune, and = probably idle rough. This becomes more of an issue with the small power wires and associated voltage drop. =20 Next, in the documentation for the EC2, the diagrams and part of the=20 text it shows that most of the wires should be run using 22 and/or 20=20 AWG wire for the connections. However, in ONE place in the document it=20 states that the power wire to the coils should be 16 AWG. =20 I don't think that's an inconsistency, perhaps a misunderstanding. I = think the 22 and 20 ga. refers to all the wiring between the PCM and the EC2; = The power leads to the coils and injectors are a separate issue. As Ed = points out, there will be undesirable voltage drop in a 20 ga, perhaps worse = than Ed mentioned because the peak currents, especially for the injectors, = will be greater than 10A. I'd also be a bit concerned about the heating in = the wires enclosed in a tube; although I'm not sure what the 'average' = current is. If it is 10 amps the 20 ga. is going to get warm up; which = increases the resistance, etc. I know it's a PITA; but if it were me, I'd bite = the bullet and change to 16 ga. =20 Oh, a final comment on progress. My cooling continues to impress me.=20 =20 I'm impressed with your cooling as well. Mine is good now, but I had to make a few changes after first flight to get it there. =20 Poco a poco, se va lejos, =20 Al ------=_NextPart_000_0009_01C9F6F9.4F711370 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

I am concerned about some sputtering that is present around idle.  It = is

generally pretty smooth, but sputters too. Not sure what is causing it =

yet.  Thoughts?

 

Don’t = know exactly you definition of sputtering, But could be a combination of = factors, including some mixture tuning required. My engine is smooth down to = about 1500, then begins to miss the occasional beat as I slow it further, and gets a = bit rough down at 1000. It might help if you can figure out why you have to = ‘pump’ the throttle to make it slow down.

 <= /font>

I don’t = have a clue about the RPM = inconsistency, but on the photo of the EM2 panel it looks like voltage is 11.1, but = can’t tell for sure.  Did you not have the field current on the = alternator? If you tune the engine with the voltage at about 14.0; then run at 11, it = will be out of tune, and probably idle rough. This becomes more of an issue with = the small power wires and associated voltage drop.

 

Next, in the documentation for the EC2, the diagrams and part of the =

text it shows that most of the wires should be run using 22 and/or 20 =

AWG wire for the connections.  However, in ONE place in the document it =

states that the power wire to the coils should be 16 AWG.

 

I don’t = think that’s an inconsistency, perhaps a misunderstanding.  I think = the 22 and 20 ga. refers to all the wiring between the PCM and the EC2; The = power leads to the coils and injectors are a separate issue. As Ed points out, there = will be undesirable voltage drop in a 20 ga, perhaps worse than Ed mentioned = because the peak currents, especially for the injectors, will be greater than = 10A.  I’d also be a bit concerned about the heating in the wires enclosed in a = tube; although I’m not sure what the ‘average’ current = is.  If it is 10 amps the 20 ga. is going to get warm up; which increases the resistance, etc.  I know it’s a PITA; but if it were me, = I’d bite the bullet and change to 16 ga.

 

Oh, a final comment on progress.  My cooling continues to impress me. =

 

I’m = impressed with your cooling as well.  Mine is good now, but I had to make a = few changes after first flight to get it there.

 

Poco a poco, = se va lejos,

 <= /font>

Al

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