X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-ma03.mx.aol.com ([64.12.206.41] verified) by logan.com (CommuniGate Pro SMTP 5.4c2o) with ESMTP id 4886760 for flyrotary@lancaironline.net; Tue, 01 Mar 2011 13:38:27 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.206.41; envelope-from=Bktrub@aol.com Received: from imo-ma02.mx.aol.com (imo-ma02.mx.aol.com [64.12.78.137]) by imr-ma03.mx.aol.com (8.14.1/8.14.1) with ESMTP id p21IbjkH022361 for ; Tue, 1 Mar 2011 13:37:45 -0500 Received: from Bktrub@aol.com by imo-ma02.mx.aol.com (mail_out_v42.9.) id q.1004.8f29db0 (55740) for ; Tue, 1 Mar 2011 13:37:41 -0500 (EST) Received: from smtprly-dc03.mx.aol.com (smtprly-dc03.mx.aol.com [205.188.170.3]) by cia-md04.mx.aol.com (v129.9) with ESMTP id MAILCIAMD047-d3c04d6d3cf11eb; Tue, 01 Mar 2011 13:37:40 -0500 Received: from webmail-d077 (webmail-d077.sim.aol.com [205.188.181.103]) by smtprly-dc03.mx.aol.com (v129.9) with ESMTP id MAILSMTPRLYDC038-d3c04d6d3cf11eb; Tue, 01 Mar 2011 13:37:37 -0500 References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: Steve Boese TDC Finder Date: Tue, 01 Mar 2011 13:37:37 -0500 X-AOL-IP: 69.84.254.253 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: bktrub@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CDA656DF7B27C4_A6C_79E33_webmail-d077.sysops.aol.com" X-Mailer: AOL Webmail 33298-STANDARD Received: from 69.84.254.253 by webmail-d077.sysops.aol.com (205.188.181.103) with HTTP (WebMailUI); Tue, 01 Mar 2011 13:37:37 -0500 Message-Id: <8CDA656DA2E55CA-A6C-3642D@webmail-d077.sysops.aol.com> X-Spam-Flag:NO X-AOL-SENDER: Bktrub@aol.com ----------MB_8CDA656DF7B27C4_A6C_79E33_webmail-d077.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="us-ascii" I still like the minumum volume method- it works even for those who cannot= count. All you have to do is look at the pretty bubbles, and when they st= op and liquid starts up the tube, you are at TDC. Brian Trubee -----Original Message----- From: Lehanover@aol.com To: Rotary motors in aircraft Sent: Mon, Feb 28, 2011 11:16 pm Subject: [FlyRotary] Re: Steve Boese TDC Finder In a message dated 2/28/2011 1:48:13 P.M. Eastern Standard Time, echristle= y@att.net writes: Al Gietzen wrote: >> Al >=20 >> >=20 > =20 >=20 I have been doing this since 1980, and that last one lost me. =20 Any method used must involve both the leading and trailing plug holes. Any= method that uses sightings of apex seals in those plug holes will be off= between 4 and 9 degrees (advanced) because the plug holes are both locate= d higher in the housing than neutral. Also the distance between plugs is= different in various housing years.=20 =20 This is good for an approximation of TDC only. Good for first start and dr= opping in the distributor or crank angle sensor. The pulley should be mark= ed with an accurate TDC and at least the maximum total advance, or lacking= that, the TDC mark and an adjustable timing light. Has the knob on the ba= ck. Costs a lot more. You rev the engine up to test RPM, say 6,000 and tur= n the knob until the TDC mark is under the pointer. Look at the pointer on= the back of the timing light it is pointing at your total advance at 6,00= 0 RPM.=20 =20 Use any minimum volume system to find an accurate TDC.=20 =20 20 to 24 degrees is plenty of advance unless have to use high octane fuel= all of the time, then 26 to 27 degrees is fine. =20 Mark the starter ring teeth with different color paint dots for TDC and ma= ximum advance. Buy an inductive (Clip on) timing light and practice using= it. =20 It was 80 today in Zephyrhills. I flew my Super Cub and BF-109 before the= wind picked up around 10:00. Not a single cloud to be seen. The sky divers were up all day. =20 Lynn E. Hanover ----------MB_8CDA656DF7B27C4_A6C_79E33_webmail-d077.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="us-ascii"
I still like the minumum= volume method- it works even for those who cannot count. All you have to= do is look at the pretty bubbles, and when they stop and liquid starts up= the tube, you are at TDC.
 
Brian Trubee



-----Original Message-----
From: Lehanover@aol.com
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Mon, Feb 28, 2011 11:16 pm
Subject: [FlyRotary] Re: Steve Boese TDC Finder

In a message dated 2/28/2011 1:48:13 P.M. Eastern Standard Time, echristley@att.net writes:
Al Gietzen wrote:
>>  Al
>
>>
>
> 
>
I have been doing this since 1980, and that last one lost me.
 
Any method used must involve both the leading and trailing plug holes= . Any method that uses sightings of apex seals in those plug holes will be= off between 4 and 9 degrees (advanced) because the plug holes are both lo= cated higher in the housing than neutral. Also the distance between plugs= is different in various housing years.
 
This is good for an approximation of TDC only. Good for first start= and dropping in the distributor or crank angle sensor. The pulley should= be marked with an accurate TDC and at least the maximum total advance, or= lacking that, the TDC mark and an adjustable timing light. Has the knob= on the back. Costs a lot more. You rev the engine up to test RPM, say 6,0= 00 and turn the knob until the TDC mark is under the pointer. Look at the= pointer on the back of the timing light it is pointing at your total adva= nce at 6,000 RPM.
 
Use any minimum volume system to find an accurate TDC.
 
20 to 24 degrees is plenty of advance unless have to use high octane= fuel all of the time, then 26 to 27 degrees is fine.
 
Mark the starter ring teeth with different color paint dots for TDC= and maximum advance. Buy an inductive (Clip on) timing light and pra= ctice using it.
 
It was 80 today in Zephyrhills. I flew my Super Cub and BF-109 before= the wind picked up around 10:00.
Not a single cloud to be seen. The sky divers were up all day.
 
Lynn E. Hanover
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