X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from willowsprings.uwyo.edu ([129.72.10.31] verified) by logan.com (CommuniGate Pro SMTP 6.0c3) with ESMTPS id 5929907 for flyrotary@lancaironline.net; Sat, 08 Dec 2012 22:09:24 -0500 Received-SPF: none receiver=logan.com; client-ip=129.72.10.31; envelope-from=SBoese@uwyo.edu Received: from ponyexpress-ht3.uwyo.edu (extlb.uwyo.edu [172.26.4.4]) by willowsprings.uwyo.edu (8.14.4/8.14.4) with ESMTP id qB938hsO029660 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL) for ; Sat, 8 Dec 2012 20:08:43 -0700 (MST) (envelope-from SBoese@uwyo.edu) Received: from ponyexpress-m10.uwyo.edu ([fe80::60dd:cb9e:6f71:3d48]) by ponyexpress-ht3.uwyo.edu ([fe80::4cde:db24:a0a9:ba5%15]) with mapi id 14.02.0318.001; Sat, 8 Dec 2012 20:08:42 -0700 From: "Steven W. Boese" To: Rotary motors in aircraft Subject: RE: [FlyRotary] Engine Ground changed from Aeroquip hose Thread-Topic: [FlyRotary] Engine Ground changed from Aeroquip hose Thread-Index: AQHN1amJBZ/R44t3h0qCgk3/e0rVNJgPuxo4 Date: Sun, 9 Dec 2012 03:08:42 +0000 Message-ID: <3E8191F276108F4481AB0721BBA9269E05EC6363@ponyexpress-m10.uwyo.edu> References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [75.220.150.226] Content-Type: multipart/alternative; boundary="_000_3E8191F276108F4481AB0721BBA9269E05EC6363ponyexpressm10u_" MIME-Version: 1.0 --_000_3E8191F276108F4481AB0721BBA9269E05EC6363ponyexpressm10u_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Bill, You are correct that my battery is in the cockpit. Since you have multiple= devices that are having problems simultaneously, it might be good to check= things that are common to all of them. The likelihood of loosing several = ground or supply connections at the same time seems remote. In other words= , check the connection of the forest of tabs to the battery ground before w= orrying about the individual tabs.. Also, since you have two batteries, it= seems unlikely that the problem would be happening within both of them at = the same time. Are the batteries connected to the positive side of the sys= tem through separate contactors? If so, are both contactors closed when th= e problem occurs? If both batteries are connected through one contactor, t= hat could be a common point of failure. Steve ________________________________ From: Rotary motors in aircraft [flyrotary@lancaironline.net] on behalf of = Bill Bradburry [bbradburry@bellsouth.net] Sent: Saturday, December 08, 2012 6:06 PM To: Rotary motors in aircraft Subject: [FlyRotary] Engine Ground changed from Aeroquip hose Steve, My two batteries are mounted on the engine side of the firewall. I presume= yours is mounted in the cockpit? I had not considered a loose connection = inside the battery. I plan to clean up all the connections outside the bat= tery. I have had a VOM connected to the supply side of the transponder when it we= nt off and I did not see any fluctuation in the voltage when that happened.= Several folks have suggested that I have a grounding issue so I am cleani= ng all of them up. I previously replaced both the power and ground wires t= o the transponder but that had no affect. I am not certain how to check each ground wire going to the forest of tabs.= Anybody have a suggestion? Bill B ________________________________ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Beh= alf Of Steven W. Boese Sent: Saturday, December 08, 2012 4:52 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Aeroquip hose Bill, From your description, your ground architecture sounds very similar to mine= . I have the forest of tabs bolted to the firewall with a brass bolt. On = the cabin side, the battery ground is connected to this bolt. Everything e= lse grounds to the forest of tabs. On the engine side of the firewall, the= engine ground is connected from the front (in the car) cover to that brass= bolt. My arrangement has not had any electrical problems that I am aware = of. I also have a stainless wire braid covered fuel line from the firewall bulk= head fitting to the fuel rail on the engine. I have seen no damage to it. = The fact that your wire braid on the fuel line has been burnt suggests tha= t it might have intermittently served as the engine ground at one time or a= nother. The braid must not have conducted a large current for very long or= it would been destroyed completely. I can't think of a worse place to hav= e an uncontrolled resistance heater than on that fuel line. Verifying the = integrity of the ground from the engine to the airframe and from the batter= y to the airframe certainly seems like a worthwhile endeavor. Depending on the details of the alternator installation, an intermittent co= nnection inside the battery also might be a possibility although this would= not explain the damage to the fuel line braid. FWIW Steve Boese RV6A, 1986 13B NA, RD1A, EC2 --_000_3E8191F276108F4481AB0721BBA9269E05EC6363ponyexpressm10u_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Bill,

 

You are correct that my battery is in the cockpit.  Since you have = multiple devices that are having problems simultaneously, it might be good = to check things that are common to all of them.  The likelihood of&nbs= p;loosing several ground or supply connections at the same time seems remote.  In other words, check the connection = of the forest of tabs to the battery ground before worrying about the individual tabs..  Also, since you have two batteries, it = seems unlikely that the problem would be happening within both of them at the same time.  Are the batteries connected to the po= sitive side of the system through separate contactors?  If so, are&nbs= p;both contactors closed when the problem occurs?  If both batter= ies are connected through one contactor, that could be a common point of failure. 

 

Steve         

From: Rotary motors in aircraft [flyrotary= @lancaironline.net] on behalf of Bill Bradburry [bbradburry@bellsouth.net]<= br> Sent: Saturday, December 08, 2012 6:06 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Engine Ground changed from Aeroquip hose

Steve,

&= nbsp;

My two batterie= s are mounted on the engine side of the firewall.  I presume yours is = mounted in the cockpit?  I had not considered a loose connection inside the battery.  I plan to clean up all the conn= ections outside the battery.

I have had a VO= M connected to the supply side of the transponder when it went off and I di= d not see any fluctuation in the voltage when that happened.  Several folks have suggested that I have a grounding = issue so I am cleaning all of them up.  I previously replaced both the= power and ground wires to the transponder but that had no affect.

&= nbsp;

I am not certai= n how to check each ground wire going to the forest of tabs.  Anybody = have a suggestion?

&= nbsp;

Bill B

&= nbsp;

From:= Rotary motors in aircraft [mailto:flyrotary@lancaironline.n= et] On Behalf Of Steven W. Boes= e
Sent: Saturday, December 08= , 2012 4:52 PM
To: Rotary motors in aircra= ft
Subject: [FlyRotary] Re: Ae= roquip hose

 

Bill,

 

From your description, your gro= und architecture sounds very similar to mine.  I have the forest = of tabs bolted to the firewall with a brass bolt.  On the cabin side, the battery ground is connected to this bolt.  Eve= rything else grounds to the forest of tabs.  On the engine side of the= firewall, the engine ground is connected from the front (in the car) = cover to that brass bolt.  My arrangement has not had any electrical problems that I am aware of.

 

I also have a stainless wire br= aid covered fuel line from the firewall bulkhead fitting to the fuel rail o= n the engine.  I have seen no damage to it.  The fact that your wire braid on the fuel line has been burnt su= ggests that it might have intermittently served as the engine ground a= t one time or another.  The braid must not have conducted a large curr= ent for very long or it would been destroyed completely.  I can't think of a worse place to have an uncontrolled resistance heater t= han on that fuel line.  Verifying the integrity of the ground from the= engine to the airframe and from the battery to the airframe certainly seem= s like a worthwhile endeavor.

 

Depending on the details of the= alternator installation, an intermittent connection inside the battery als= o might be a possibility although this would not explain the damage to the fuel line braid.

 

FWIW

 

Steve Boese=

RV6A, 1986&= nbsp;13B NA, RD1A, EC2

     &= nbsp;  

 

 

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