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 5.0c3) with ESMTP id 748077 for flyrotary@lancaironline.net; Tue, 04 Oct 2005 19:52:44 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-025-165.carolina.res.rr.com [24.74.25.165]) by ms-smtp-02-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j94Nptl9020475 for ; Tue, 4 Oct 2005 19:51:57 -0400 (EDT) Message-ID: <53ac01c5c93e$749738b0$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Telling rotors apart - Never trust Atkins! Date: Tue, 4 Oct 2005 19:50:52 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_53A9_01C5C91C.ED372A90" 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_53A9_01C5C91C.ED372A90 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Dave, I am going to have to dig through my note book out in the = workshop. But,if memory serves me correct, the 9.7:1 measures 4mm from = the bottom of a straight edge across the face (long way) at its deepest = part of the compression cavity. Again, I will check my note book and get back to you but I think the = 9.4:1 measured around 5- 5 1/2 mm and the 9.1:1 measured at 7mm. Ed A ----- Original Message -----=20 From: David Leonard=20 To: Rotary motors in aircraft=20 Sent: Tuesday, October 04, 2005 7:21 PM Subject: [FlyRotary] Telling rotors apart - Never trust Atkins! On 9/28/05, Kelly Troyer wrote:=20 Ed Anderson has a measurement to check the depth of the combustion = depression in the face of the rotor to determine the compression ratio (the deeper one = is turbo)....... How about it Ed, any info on this? Can it be used to tell the 9.4:1 = 86-88 rotors from the 9.7:1 rotors? Bottom line check weight first then check the depth of the = combustion depression........I have another way I use to determine what year my rotors are (all my = engines are NA 86 to 91).....The combustion depression in the 86 to 88 is as cast in the rotor = (slight grainy surface finish).....The 89-91 depression is machined and has straight machine marks....... That is really interesting. My old rotors are supposed to be 1991 T2 = rotors but they have the cast appearance (However since I got them from = Atkins I am not really sure they gave me what they sold me). The rotors = that Earnest sent also have a cast appearance. But as I recall, the = rotors in the engine I rebuilt had the milling marks... hmmm.. if = that is true the balance in my current engine is all SNAFU. Are you = sure that system is a valid way to do the measuring?=20 So I just got back from weighing my rotors - Sure enough, the ones = Atkins sold me weighted in at 10.20 and 10.19 making them the 86-88 = variety despite the fact that I paid for a '91 engine. Worse, I have no = idea what counter-weights he decided to use. If it matched the rotors = he sold me then I have been running an unbalanced engine for the last = 150 hrs. (that explains part of why the wife won't fly in it)=20 Does anyone know what the correct weights of the counter weights = should be for a given year group? Or perhaps some other way of telling = them apart? BTW Ernest, the rotors you sent also weigh in at 10.18. Dave Leonard Check with Ed for his method to determine compression ratio as I = do not have it at hand......I am attaching the rotor weight chart from "Mazdatrix" which will help = (note weight does not include any seals or springs....just the bearing.........Hope this = helps........Any more questions just ask !!=20 -- Kelly Troyer=20 Dyke Delta/13B/RD1C/EC2=20 =20 Engine Year Compression Weight (Grams) Weight (Pounds)=20 12A 76-82 9.4 4603 10.15=20 12A 83-85 9.4 4353 9.60=20 13B 74-78 9.2 5253 11.58=20 13B 84-85 9.4 5253 11.58=20 13B N/T 86-88 9.4 4553 10.04=20 13B Turbo 86-88 8.5 4553 10.04=20 13B N/T 89-92 9.7 4328 9.54=20 13B Turbo 89-92 9.0 4328 9.54=20 13B T/T 93-95 9.0 4328 9.54=20 NOTE: Weights are approximate, and include rotor bearing, but do not = include any seals or springs.=20 --=20 Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/_ht_a/vp4skydoc/index.html ------=_NextPart_000_53A9_01C5C91C.ED372A90 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Dave, I am going to have to dig through my note = book out=20 in the workshop.  But,if memory serves me correct, the 9.7:1 = measures 4mm=20 from the bottom of a straight edge across the face (long way) at its = deepest=20 part of the compression cavity.
 
Again, I will check my note book and get back to = you but I=20 think the 9.4:1 measured around 5- 5 1/2 mm and the 9.1:1 measured at=20 7mm.
 
Ed A
----- Original Message -----
From:=20 David=20 Leonard
Sent: Tuesday, October 04, 2005 = 7:21=20 PM
Subject: [FlyRotary] Telling = rotors apart=20 - Never trust Atkins!


On 9/28/05, Kelly=20 Troyer <keltro@att.net> = wrote:=20
 
  Ed Anderson has a measurement to check the depth of the=20 combustion depression in the
face of the rotor to determine the compression ratio (the = deeper one is=20 turbo).......
 
How about it Ed, any info on this?  Can it be used to tell = the 9.4:1=20 86-88 rotors from the 9.7:1  rotors?

 Bottom line check weight first then check the depth of = the=20 combustion depression........I have
another way I use to determine what year my rotors are (all my = engines=20 are NA 86 to 91).....The
combustion depression in the 86 to 88 is as cast in the rotor = (slight=20 grainy surface finish).....The
89-91 depression is machined and has straight machine=20 marks.......
 
That is really interesting.  My old rotors are supposed to = be 1991=20 T2 rotors but they have the cast appearance (However since I got them = from=20 Atkins I am not really sure they gave me what they sold me).  The = rotors=20 that Earnest sent also have a cast appearance.  But as I recall, = the=20 rotors in the engine I rebuilt had the milling marks...  =20 hmmm..  if that is true the balance in my current engine is all=20 SNAFU.  Are you sure that system is a valid way to do the = measuring?=20
 
So I just got back from weighing my rotors - Sure enough, the = ones Atkins=20 sold me weighted in at 10.20 and 10.19 making them the 86-88 variety = despite=20 the fact that I paid for a '91 engine.  Worse, I have no idea = what=20 counter-weights he decided to use.  If it matched the rotors he = sold me=20 then I have been running an unbalanced engine for the last 150 = hrs. =20 (that explains part of why the wife won't fly in it)
 
Does anyone know what the correct weights of the counter weights = should=20 be for a given year group?  Or perhaps some other way of telling = them=20 apart?
 
BTW Ernest, the rotors you sent also weigh in at 10.18.
 
Dave Leonard

  Check with Ed for his method to determine compression = ratio as I=20 do not have it at hand......I
am attaching the rotor weight chart from "Mazdatrix" which will = help=20 (note weight does not
include any seals or springs....just the bearing.........Hope = this=20 helps........Any more questions
just ask !! 
 
--
Kelly Troyer
Dyke Delta/13B/RD1C/EC2 =
 
Engine Year Compression Weight (Grams) Weight (Pounds)
12A 76-82 9.4 4603 10.15
12A 83-85 9.4 4353 9.60
13B 74-78 9.2 5253 11.58
13B 84-85 9.4 5253 11.58
13B N/T 86-88 9.4 4553 10.04
13B Turbo 86-88 8.5 4553 10.04
13B N/T 89-92 9.7 4328 9.54
13B Turbo 89-92 9.0 4328 9.54
13B T/T 93-95 9.0 4328 9.54

NOTE: Weights are approximate, and include rotor bearing, = but do=20 not include any seals or springs.=20



--
Dave=20 Leonard
Turbo Rotary RV-6 N4VY
http://members.aol.com/_ht_a/rotaryroster/index.html<= BR>http://members.aol.com/_ht_a/vp4skydoc/index.html=20 ------=_NextPart_000_53A9_01C5C91C.ED372A90--