X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail09.syd.optusnet.com.au ([211.29.132.190] verified) by logan.com (CommuniGate Pro SMTP 5.0.6) with ESMTPS id 931819 for flyrotary@lancaironline.net; Wed, 18 Jan 2006 16:10:46 -0500 Received-SPF: none receiver=logan.com; client-ip=211.29.132.190; envelope-from=lendich@optusnet.com.au Received: from george (d220-236-170-90.dsl.nsw.optusnet.com.au [220.236.170.90]) by mail09.syd.optusnet.com.au (8.12.11/8.12.11) with SMTP id k0IL9oZe028887 for ; Thu, 19 Jan 2006 08:09:55 +1100 Message-ID: <002c01c61c73$88ef9fe0$5aaaecdc@george> From: "george lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] LS1 Coil Failures Date: Thu, 19 Jan 2006 07:09:55 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0029_01C61CC7.59A8C460" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 This is a multi-part message in MIME format. ------=_NextPart_000_0029_01C61CC7.59A8C460 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Ed, A little feed-back from local after market suppliers here in Australia. They don't supply after market coils for GMH (GMC) vehicles which use = the LS1's as they hardly ever need replacement! The GMH genuine is prohibitively expensive and it is impossible to get = aftermarket, that's why we have a problem with local supply! George (down under)=20 Hummm, think I will hold off swapping my stock Mazda Coils for the = LS1s sitting on my work bench until we have a better handle on the coil = "problem". Have now flow for 300 + hours and over six years with the = stock coils with the only problem being the early failure of the leading = module because of a resistor opening in its base. =20 The wattage of the resistor is apparently too low to carry the load of = the ignition continuously running at 6000+ rpm. Replaced the resistor = with a higher wattage one and no more problem. At least three people = have had this resistor fail using the stock coils - it may well be that = the auto folks don't design for their coils to be run at high continuous = rpms unlike the MSD type ignitions for racing.=20 I wonder what the automobile circle are experiencing with their LS1 = coils - anyone know? Ed A ----- Original Message -----=20 From: al p wick=20 To: Rotary motors in aircraft=20 Sent: Wednesday, January 18, 2006 9:57 AM Subject: [FlyRotary] Re: Coil & Alt cooling, Buly's input shaft 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. =20 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 ------=_NextPart_000_0029_01C61CC7.59A8C460 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Ed,
A little feed-back from local after market suppliers here in=20 Australia.
 
They don't supply after market coils for GMH (GMC) vehicles which = use the=20 LS1's as they hardly ever need replacement!
 
The GMH genuine is prohibitively expensive and it is = impossible to get=20 aftermarket, that's why we have a problem with local supply!
George (down under) 

Hummm, think I will hold off swapping = my stock=20 Mazda Coils for the LS1s sitting on my work bench until we have a = better=20 handle on the coil "problem".  Have now flow for 300 + hours and = over six=20 years with the stock coils with the only problem being the early = failure of=20 the leading module because of a resistor opening in its base. =20
 
The wattage of the resistor is = apparently too low=20 to carry the load of the ignition continuously running at 6000+ = rpm. =20 Replaced the resistor with a higher wattage one and no more = problem.  At=20 least three people have had this resistor fail using the stock coils - = it may=20 well be that the auto folks don't design for their coils to be run at = high=20 continuous rpms unlike the MSD type ignitions for = racing. 
 
I wonder what the automobile circle = are=20 experiencing with their  LS1 coils - anyone know?
 
 
Ed A
----- Original Message -----
From:=20 al p = wick
To: Rotary motors in = aircraft=20
Sent: Wednesday, January 18, = 2006 9:57=20 AM
Subject: [FlyRotary] Re: Coil = & Alt=20 cooling, Buly's input shaft

I'm wondering if 180f under hood is really the main cause for = coil=20 fail? Auto's shut off hot in desert, black steel hood, must see = temps way=20 beyond anything we can throw at them. You can't get those puppies to = fail=20 regardless of environment. Perhaps there are one or two other = significant=20 causes. I'd be real 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=20 design info:
htt= p://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 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=20 is made from a Tupperware container pirated from the kitchen with = a skirt=20 made from sheet silicone rubber.  A 5/8" ID vinyl hose routes = cool=20 air from the oil cooler plenum to it.   ( 3/8" ID hose = was tried=20 first, not quite good enough)  This was tried prior to = today's=20 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=20 tupperware) and fed by a 3/8" ID hose but it was pretty leaky = and=20 only dropped temps about 10 - 15 degrees.  After replacing = the coil=20 today I built a better fitting plenum and fed it with 5/8" ID = hose. =20 This one is made of space-age cardboard and I'll build a more = permanent=20 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=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=20 look as if there is misalignment between the E-shaft  and the = gear=20 drive.  When you built the plate & bellhousing adapter = for the=20 drive, how did you verify concentricity?  This is much harder = to do=20 than verifying the parallelism of the bellhousing and plate but is = absolutely vital.  There is no question that the drive would = have=20 soon failed if you had continued to run it.   Glad this = showed=20 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 = engine/airframe from Portland, Oregon
Prop construct, Subaru = install,=20 Risk assessment, Glass panel design=20 = info:
http://www.maddyhome.com/canardpages/pages/alwick/index.html
=
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