X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 24 May 2012 12:45:17 -0400 Message-ID: X-Original-Return-Path: Received: from mail-gg0-f180.google.com ([209.85.161.180] verified) by logan.com (CommuniGate Pro SMTP 5.4.5) with ESMTPS id 5557981 for lml@lancaironline.net; Thu, 24 May 2012 11:57:15 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.180; envelope-from=pjdmiller@gmail.com Received: by ggnf1 with SMTP id f1so7793116ggn.25 for ; Thu, 24 May 2012 08:56:41 -0700 (PDT) Received: by 10.236.173.37 with SMTP id u25mr9746388yhl.56.1337875001733; Thu, 24 May 2012 08:56:41 -0700 (PDT) X-Original-Return-Path: Received: from [192.168.15.102] ([67.8.30.163]) by mx.google.com with ESMTPS id l13sm47268098ann.2.2012.05.24.08.56.40 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 24 May 2012 08:56:40 -0700 (PDT) Subject: Re: [LML] Re: B&C sd-20 backup alternator References: From: Paul Miller Content-Type: text/plain; charset=us-ascii X-Mailer: iPad Mail (9B206) In-Reply-To: X-Original-Message-Id: <710B4D03-47F7-4BD7-A651-AFA50A81F684@gmail.com> X-Original-Date: Thu, 24 May 2012 11:56:40 -0400 X-Original-To: Lancair Mailing List Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (1.0) I don't see any relationship. I run mine 100% of the time to power the esse= ntial bus batteries. The bearing failure would not be affected by power. T= he broken leads are all at handling points where some worker has tweaked the= wire. I believe the accessory drive spins at 150% of engine rpm so it would= be seeing about 3500 rpm, which is only half the speed of the primary alter= nator. It does not appear to be an overworked device at that speed and 20 a= mps. Paul On 2012-05-24, at 10:43, Colyn Case wrote: > I'll add it to my list. > Have you figured out if there is a relationship to the % of time the stand= by alternator is energized and how soon it fails? > I've been running mine all the time. >=20 >=20 > On May 23, 2012, at 1:17 PM, Paul Miller wrote: >=20 > Colyn: No need. Found the open circuit winding while pondering how the s= tator could fail inside that big hunk of metal. See picture for third brok= en stator winding. I can fix those breaks. Brushes and bearings and stators= are readily available, as you suggest, for these units as they do power a n= umber of applications from Toyota to Kubota. I believe they are available d= omestically (N.A.). If it were my shop, I'd implement a 500 hour recommend= ed inspection just like the magnetos. They go in the shop, get cleaned up, p= arts get checked and replaced as necessary and everyone is happy. That's a= lot better than in-plane failure. The shop gets revenue, better understand= ing of the weak points and avoids do-it-yourselfers like me taking things ap= art. I'd be very happy to have Bill go through this thing every 500 hours a= nd replace what needs replacing and I have written him with that suggestion.= Thanks for the idea. >=20 > Paul >=20 > On 2012-05-23, at 11:17 AM, Colyn Case wrote: >=20 >> Paul, >>=20 >> My understanding: Bill sources the parts in China or Japan, balances ever= ything and maybe tweaks a couple other things, and then puts his name on it.= Given the stator doesn't need to be balanced, could you find the oversea= s source and solve your problem that way? >>=20 >> Colyn >>=20 > -- > For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.htm= l >=20 >=20 > -- > For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.htm= l