X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from m12.lax.untd.com ([64.136.30.75] verified) by logan.com (CommuniGate Pro SMTP 5.0.6) with SMTP id 931352 for flyrotary@lancaironline.net; Wed, 18 Jan 2006 10:00:01 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.136.30.75; envelope-from=alwick@juno.com Received: from m12.lax.untd.com (localhost [127.0.0.1]) by m12.lax.untd.com with SMTP id AABB66X65A2KVRRS for (sender ); Wed, 18 Jan 2006 06:58:35 -0800 (PST) Received: (from alwick@juno.com) by m12.lax.untd.com (jqueuemail) id LEZPENWF; Wed, 18 Jan 2006 06:57:58 PST To: flyrotary@lancaironline.net Date: Wed, 18 Jan 2006 06:57:40 -0800 Subject: Re: [FlyRotary] Re: Coil & Alt cooling, Buly's input shaft Message-ID: <20060118.065752.1448.3.alwick@juno.com> X-Mailer: Juno 5.0.33 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary=--__JNP_000_4a1d.120d.3bbb X-Juno-Line-Breaks: 8-6,11-21,24-25,34-35,41-44,55-63,64-32767 From: al p wick X-ContentStamp: 3:4:2503226632 X-MAIL-INFO:4f858504112571797414b904d9b98075454130b940a4351d11403041408140151929c4898521045d047d113980e101397925f529ed6d34bdd53da55075d43dcd84b1f5cd95 X-UNTD-OriginStamp: L941HVjjYzDhN3itp//mkEEXYbt1nk2yINhK8fNEVYJyyd9jdHowFg== X-UNTD-Peer-Info: 127.0.0.1|localhost|m12.lax.untd.com|alwick@juno.com This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ----__JNP_000_4a1d.120d.3bbb Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit I'm wondering if 180f under hood is really the main cause for coil fail? Auto's shut off hot in desert, black steel hood, must see temps way beyond anything we can throw at them. You can't get those puppies to fail regardless of environment. Perhaps there are one or two other significant causes. I'd be real quick to abandon that manufacturer. -al wick Artificial intelligence in cockpit, Cozy IV powered by stock Subaru 2.5 N9032U 200+ hours on engine/airframe from Portland, Oregon Prop construct, Subaru install, Risk assessment, Glass panel design info: http://www.maddyhome.com/canardpages/pages/alwick/index.html On Tue, 17 Jan 2006 22:39:15 -0500 "Tracy Crook" writes: During my preflight tests this morning I found the third failed ignition coil in the last 150 hours so I finally got serious about dropping the temps around my coils and alternator. I've been concerned about this since the under-cowl temps are as high as 180 deg F (delta T through rads is 70 - 90 deg F). The attached photo shows the solution (hopefully). The alternator plenum is made from a Tupperware container pirated from the kitchen with a skirt made from sheet silicone rubber. A 5/8" ID vinyl hose routes cool air from the oil cooler plenum to it. ( 3/8" ID hose was tried first, not quite good enough) This was tried prior to today's scrubbed flight and a temp probe shows that air inlet temps to the alternator are only 3 - 5 degrees above ambient. Nice. I had recently added a cooling plenum around the coils (also made of tupperware) and fed by a 3/8" ID hose but it was pretty leaky and only dropped temps about 10 - 15 degrees. After replacing the coil today I built a better fitting plenum and fed it with 5/8" ID hose. This one is made of space-age cardboard and I'll build a more permanent one from fiberglass if it works OK. Will test tomorrow if wx allows. Input shaft Buly, got your input shaft today and checked it out. The thrust bearing rollers & races look a little stressed but the roller cage has been completely trashed. I do not think the .005" out of flatness on your bellhousing would explain this and the odd wear pattern on the plate. The marks and discoloration (heat) on the bearing and shaft look as if there is misalignment between the E-shaft and the gear drive. When you built the plate & bellhousing adapter for the drive, how did you verify concentricity? This is much harder to do than verifying the parallelism of the bellhousing and plate but is absolutely vital. There is no question that the drive would have soon failed if you had continued to run it. Glad this showed up before flight. Tracy (Happy to hear that Dave L. is safe! Good flying. ) -al wick Artificial intelligence in cockpit, Cozy IV powered by stock Subaru 2.5 N9032U 200+ hours on engine/airframe from Portland, Oregon Prop construct, Subaru install, Risk assessment, Glass panel design info: http://www.maddyhome.com/canardpages/pages/alwick/index.html ----__JNP_000_4a1d.120d.3bbb Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: quoted-printable
I'm wondering if 180f under hood is really the main cause for coil = fail?=20 Auto's shut off hot in desert, black steel hood, must see temps way beyond= =20 anything we can throw at them. You can't get those puppies to fail = regardless of=20 environment. Perhaps there are one or two other significant causes. I'd be = real=20 quick to abandon that manufacturer.
 

-al wick
Artificial intelligence in cockpit, Cozy IV powered by= =20 stock Subaru 2.5
N9032U 200+ hours on engine/airframe from Portland,=20 Oregon
Prop construct, Subaru install, Risk assessment, Glass panel = design=20 info:
http:= //www.maddyhome.com/canardpages/pages/alwick/index.html
 
On Tue, 17 Jan 2006 22:39:15 -0500 "Tracy Crook" <lors01@msn.com> writes:
During my preflight tests this morning I found the third failed= =20 ignition coil in the last 150 hours so I finally got serious about = dropping=20 the temps around my coils and alternator.  
 
I've been concerned about this since the under-cowl temps are = as=20 high as 180 deg F (delta T through rads is 70 - 90 deg F).  The= =20 attached photo shows the solution (hopefully).  The alternator = plenum is=20 made from a Tupperware container pirated from the kitchen with a skirt = made=20 from sheet silicone rubber.  A 5/8" ID vinyl hose routes cool air = from=20 the oil cooler plenum to it.   ( 3/8" ID hose was tried first, = not=20 quite good enough)  This was tried prior to today's scrubbed = flight=20 and a temp probe shows that air inlet temps to the alternator are only 3 = - 5=20 degrees above ambient.  Nice.
 
I had recently added a cooling plenum around the coils (also made of= =20 tupperware) and fed by a 3/8" ID hose but it was pretty leaky and = only=20 dropped temps about 10 - 15 degrees.  After replacing the coil today= I=20 built a better fitting plenum and fed it with 5/8" ID hose.  This = one is=20 made of space-age cardboard and I'll build a more permanent one from=20 fiberglass if it works OK.  Will test tomorrow if wx allows.
 
Input shaft
 
Buly, got your input shaft today and checked it out.  The = thrust=20 bearing rollers & races look a little stressed but the roller cage = has=20 been completely trashed.  I do not think the .005" out of flatness = on=20 your bellhousing would explain this and the odd wear pattern on the=20 plate.  The marks and discoloration (heat) on the bearing and shaft = look=20 as if there is misalignment between the E-shaft  and the gear=20 drive.  When you built the plate & bellhousing adapter for the = drive,=20 how did you verify concentricity?  This is much harder to do than=20 verifying the parallelism of the bellhousing and plate but is absolutely= =20 vital.  There is no question that the drive would have soon failed = if you=20 had continued to run it.   Glad this showed up before flight.
 
Tracy  (Happy to hear that Dave L. is safe!  Good=20 flying. )
 

-al wick
Artificial intelligence in= =20 cockpit, Cozy IV powered by stock Subaru 2.5
N9032U 200+ hours on=20 engine/airframe from Portland, Oregon
Prop construct, Subaru install, = Risk=20 assessment, Glass panel design=20 info:
http://www.maddyhome.com/canardpages/pages/alwick/index.html
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