X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 11 Oct 2010 12:13:18 -0400 Message-ID: X-Original-Return-Path: Received: from mis005-1.exch005intermedia.net ([64.78.17.177] verified) by logan.com (CommuniGate Pro SMTP 5.3.9) with ESMTP id 4500425 for lml@lancaironline.net; Sun, 10 Oct 2010 12:01:33 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.78.17.177; envelope-from=johnwcox@pacificnw.com Received: from EXVBE005-2.exch005intermedia.net ([10.254.1.74]) by mis005-1.exch005intermedia.net with Microsoft SMTPSVC(6.0.3790.4675); Sun, 10 Oct 2010 09:00:42 -0700 Received: from 24.20.69.96 ([24.20.69.96]) by EXVBE005-2.exch005intermedia.net ([10.254.1.73]) via Exchange Front-End Server owa5.intermedia.net ([10.254.1.43]) with Microsoft Exchange Server HTTP-DAV ; Sun, 10 Oct 2010 16:00:42 +0000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_114400_392232880.1286647968223" Subject: RE: [LML] Slick Magneto and Spark Plugs From: John Cox In-Reply-To: References: X-Original-To: Lancair Mailing List Thread-Topic: [LML] Slick Magneto and Spark Plugs Thread-Index: ActolFCLIi1sxRwhTGi3p9O82brcLw== X-Original-Message-ID: X-Mailer: Microsoft Outlook Web Access 6.5.7651.60 X-MimeCtl: Produced By Microsoft Exchange V6.5.7651.60 X-Original-Date: Sun, 10 Oct 2010 09:00:52 -0700 X-Original-Return-Path: johnwcox@pacificnw.com X-OriginalArrivalTime: 10 Oct 2010 16:00:42.0952 (UTC) FILETIME=[4ACBF480:01CB6894] ------=_Part_114400_392232880.1286647968223 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable During one of my Inspector Authorization renewal sessions I too was fascina= ted by this proclamation by them. I began regularly checking internal resi= stance after cleaning and gap resetting. Twice I have replaced plugs for c= ustomers when they were way out of the norm. At OSH '09, asked this of the Champion Rep as well as my regular magneto r= epair shop, during dual Slick rebuilds at 500 hours. They did not laugh bu= t both said the policy is not supported by Champion. Voltage is pressure. Pressure restricts flow. Flow is energy delivery. Mo= re energy, correctly timed and delivered equates to more complete combustio= n. There is a lot of wisdom in Aircraft Magneto Service suggestions but YM= MV. Plugs used for limited minutes of time while never leaving the airport traf= fic pattern can do a lot of exciting things =3D once a year. Have you trie= d to run the boost that they do? Follow your OEMs suggested procedure. John Cox From: Isaac Heizer Sent: Sun 10/10/2010 7:57 AM To: lml@lancaironline.net Subject: [LML] Slick Magneto and Spark Plugs I had a very interesting telephone conversation Friday with a fellow from "= Aircraft Magneto Service" of Bainbridge Island, Washington (www.aircraftmag= netoservice.calls.net). It was prompted by the 350 hour inspection of the = dual pressurized Slick magnetos on my TSIO-550E. Parts are needed for both mags, but one mag shows signs of having more trap= ped moisture than the other one. In particular, the mag with the tach sens= or has more rusty discoloration than the one without the tach sensor. Appa= rently this is because the mag needs to be able to vent the pressurization = air to get a steady air exchange and when a mag's aluminum plug normally co= ntaining the .020 vent hole is replaced with the tach sensor -- the .020 ho= le is gone. The person at Aircraft Magneto Service recommended drilling an= .020 vent hole in the magneto body to restore the venting. Actually, he r= ecommended drilling the hole in the tach sensor body....but i'm afraid i'll= drill through something and ruin the sensor. Has anybody heard of or done= this? Then we started talking about spark plugs: I mentioned my plane has Champi= on fine wire plugs. He said all plugs have an internal resistor, and for s= ome reason the resistance of many Champion plugs seems to increase as the p= lug ages. Once the plug has been cleaned, the resistance can be measured w= ith a standard ohm meter between the center electrode and the connection in= side the plug barrel -- all new plugs should have a resistance somewhere ar= ound 800 - 1200 ohms. If the resistance ever measures above 5000 ohms, the= plug should not be used. The fellow told me plugs having too high of a re= sistance can/will cause misfiring and potential problems with the magneto c= oil and or plug harness. A spark plug bomb tester might show this plug as = good, so the ohm meter test should always be performed every time the plugs= are serviced. Unlike an Autolite plug, a Champion spark plug resistor can be changed. Lo= ok inside the barrel of a Champion plug and notice the slotted screw. Remo= ve the screw and the resistor will fall out: it looks like a slug of carbo= n about 1/2 inch long and maybe 1/8 inch diameter. You can put the ohm met= er on either end of this slug and measure the resistance -- this is the ele= ment that needs to measure from about 800 to 5000 ohms. The resistor is ap= parently common among all Champion plugs so he recommended visiting your pi= le of old plugs; removing the resistors; and saving the resistors that meas= ure "good". When you run across an otherwise servicable plug whose resista= nce is too high you can change its resistor for one from the "good" pile. = He says this can cure a host of otherwise mysterious "rough running" proble= ms and forestall future problems. He said some Reno racers remove the resistor and replace it with a piece of= copper wire to get a much hotter spark for racing. Says it wears out the = spark plugs very quickly -- but does make a performance difference. Is thi= s true? -isaac ES-P N7842K ------=_Part_114400_392232880.1286647968223 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
During one of my= Inspector Authorization renewal sessions I too was fascinated by this proc= lamation by them.  I began regularly checking internal resistance afte= r cleaning and gap resetting.  Twice I have replaced plugs for custome= rs when they were way out of the norm.
 
At OSH '09,  asked this of the Champ= ion Rep as well as my regular magneto repair shop, during dual Slick rebuil= ds at 500 hours.  They did not laugh but both said the policy is not s= upported by Champion.
 
Voltage is pressure.  Pressure restr= icts flow.  Flow is energy delivery. More energy, correctly timed and = delivered equates to more complete combustion.  There is a lot of wisd= om in Aircraft Magneto Service suggestions but YMMV.
 
Plugs used for limited minutes of time wh= ile never leaving the airport traffic pattern can do a lot of exciting thin= gs =3D once a year.  Have you tried to run the boost that they do?&nbs= p; Follow your OEMs suggested procedure.
 
John Cox

From: Isaac Heizer
Sent: Sun = 10/10/2010 7:57 AM
To: lml@lancaironline.net
Subject: [= LML] Slick Magneto and Spark Plugs

I had a = very interesting telephone conversation Friday with a fellow from "Aircraft= Magneto Service" of Bainbridge Island, Washington (www.aircraftmagnetoserv= ice.calls.net).  It was prompted by the 350 hour inspection of the dua= l pressurized Slick magnetos on my TSIO-550E.

Parts are needed for b= oth mags, but one mag shows signs of having more trapped moisture than the = other one.  In particular, the mag with the tach sensor has more rusty= discoloration than the one without the tach sensor.  Apparently this = is because the mag needs to be able to vent the pressurization air to get a= steady air exchange and when a mag's aluminum plug normally containing the= .020 vent hole is replaced with the tach sensor -- the .020 hole is gone.&= nbsp; The person at Aircraft Magneto Service recommended drilling an .020 v= ent hole in the magneto body to restore the venting.  Actually, he rec= ommended drilling the hole in the tach sensor body....but i'm afraid i'll d= rill through something and ruin the sensor.  Has anybody heard of or d= one this?

Then we started talking about spark plugs:  I mention= ed my plane has Champion fine wire plugs.  He said all plugs have an i= nternal resistor, and for some reason the resistance of many Champion plugs= seems to increase as the plug ages.  Once the plug has been cleaned, = the resistance can be measured with a standard ohm meter between the center= electrode and the connection inside the plug barrel -- all new plugs shoul= d have a resistance somewhere around 800 - 1200 ohms.  If the resistan= ce ever measures above 5000 ohms, the plug should not be used.  The fe= llow told me plugs having too high of a resistance can/will cause misfiring= and potential problems with the magneto coil and or plug harness.  A = spark plug bomb tester might show this plug as good, so the ohm meter test = should always be performed every time the plugs are serviced.

Unlike= an Autolite plug, a Champion spark plug resistor can be changed.  Loo= k inside the barrel of a Champion plug and notice the slotted screw.  = Remove the screw and the resistor will fall out:  it looks like a slug= of carbon about 1/2 inch long and maybe 1/8 inch diameter.  You can p= ut the ohm meter on either end of this slug and measure the resistance -- t= his is the element that needs to measure from about 800 to 5000 ohms. = The resistor is apparently common among all Champion plugs so he recommend= ed visiting your pile of old plugs; removing the resistors; and saving the = resistors that measure "good".  When you run across an otherwise servi= cable plug whose resistance is too high you can change its resistor for one= from the "good" pile.  He says this can cure a host of otherwise myst= erious "rough running" problems and forestall future problems.

He sa= id some Reno racers remove the resistor and replace it with a piece of copp= er wire to get a much hotter spark for racing.  Says it wears out the = spark plugs very quickly -- but does make a performance difference.  I= s this true?

-isaac
ES-P N7842K
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