X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-ma02.mx.aol.com ([64.12.206.40] verified) by logan.com (CommuniGate Pro SMTP 6.0.4) with ESMTP id 6181411 for flyrotary@lancaironline.net; Thu, 04 Apr 2013 18:20:21 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.206.40; envelope-from=Lehanover@aol.com Received: from mtaomg-mb06.r1000.mx.aol.com (mtaomg-mb06.r1000.mx.aol.com [172.29.41.77]) by imr-ma02.mx.aol.com (Outbound Mail Relay) with ESMTP id D14061C000078 for ; Thu, 4 Apr 2013 18:19:44 -0400 (EDT) Received: from core-mod003b.r1000.mail.aol.com (core-mod003.r1000.mail.aol.com [172.29.196.9]) by mtaomg-mb06.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 6E3B5E000089 for ; Thu, 4 Apr 2013 18:19:44 -0400 (EDT) From: Lehanover@aol.com Full-name: Lehanover Message-ID: <4d0c4.5d1d8727.3e8f567f@aol.com> Date: Thu, 4 Apr 2013 18:19:44 -0400 (EDT) Subject: Re: [FlyRotary] Re: Replacement for Aeroquip fuel hose To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_4d0c4.5d1d8727.3e8f567f_boundary" X-Mailer: AOL 9.7 sub 55 X-Originating-IP: [173.88.28.139] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1365113984; bh=zxQ3VfBPtx/1yv55MThWzDMsK14qlmawtn0PAN0zRPk=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=HvBmrKbWcnzQnplswgxMVEWaOEuNiiE/D2zCJ04s/wbZ7SA1HA0gPUfd1hQE4qYRG 13HZGnH3Zf3eVCjBz5m6k7eg6AD4xXWlDo6cKsAzBhjUzQwNuzN6MD4dwNdxD9JQKU jiq1eT4AL9D6k9YG+1ST6Dw2MsVQfeGfITLhAf8g= X-AOL-SCOLL-SCORE: 0:2:447062496:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d294d515dfc805776 --part1_4d0c4.5d1d8727.3e8f567f_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Cranking amps may exceed 110. If a bulkhead fitting is used you might well be using the hose as a parallel path with your ground strap. This is more than enough current to weld steel tubing. If one start were attempted with the ground strap loose you have used the braid as your ground. In the racer the battery ground strap bolts on with one of the starter bolts. The mating surfaces between the starter and the engine must be free of dirt and paint. Most people choose the Teflon lined hose assemblies for weight savings. Both Aeroquip and others have Nitrile liners and double stainless braid. Even a cloth cover so as not to saw through an important part or other hoses. Also the SAE specs have similar hoses at far lower cost. You must maintain similar fittings as one is a 45 degree fitting and the other is a 30 degree. Any hose shop can set you up with swaged hose ends and test them to 1,000 PSI if you like. The stainless braid looks racy but you see very little of it on real airplanes. Lynn E. Hanover In a message dated 4/4/2013 4:45:18 P.M. Eastern Daylight Time, bbradburry@bellsouth.net writes: Good points all, Rich. I am basically doing the conditional now. I have the cowl off and am only running the engine to improve the tuning. That is why I was inquiring about recommendations for fuel hose. With the cowl off, there is a fairly stiff breeze that carries away any fuel vapor. I do suspect that there was some kind of path of least resistance that caused this problem originally. I now have two #4 welding cables attached from each battery to each side of the starter which is mounted on the PSRU plate. During this conditional, I plan to attach about a 12 ga wire from the center iron to each battery just in case the ignition ground is looking for a better path due to the sandwich you mention. Bill B ____________________________________ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of ARGOLDMAN@aol.com Sent: Thursday, April 04, 2013 4:22 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Replacement for Aeroquip fuel hose Bill, This probably goes without saying, but it is vital to determine why the arcing is happening. this may be a tremendous safety issue for you (and others) Arching does not happen in a vacuum (actually it is easier there) but there is a reason. It is possible that your electrical system is using your FUEL lines ( spelled lines full of FUEL) for the grounding of somewhat high amperage loads, such as starter or alternator. One thing to ascertain is " is your engine adequately grounded". The engine mount is a poor conductor. you need a good grounding strap (line) between the "-" of your battery and the case of the engine. Since our engines are sandwiches and there is a possibility (possibly remote) that there is some resistance between the bread and the meat, your current, wanting the path of least resistance may be using those fuel lines. Perhaps you need a better ground to the mounting bolts of your starter and/or alternator. I donnknow, if it were me, I would do the fuel line inspection, correction and replacement NOW, before further starting of the engine. By the way, what is your rationale for delaying until the next conditional to correct a problem where there may be significant current flowing through your fuel lines, especially when there is a fuel smell. You don't smell liquid fuel, you smell the vapor. Lessee vapor mixed with fuel in the proper proportions with some& sort of ignition system --lets say an electric shock-- may make your next conditional inspection unnecessary. Keep safe and fly safely Rich In a message dated 4/4/2013 3:01:53 P.M. Central Daylight Time, bbradburry@bellsouth.net writes: I have several black spots on the SS braid for my fuel hoses they look like they were caused by an electrical arc? I think I can smell fuel around the spots. I plan to replace them at the conditional this month. What fuel hoses are being used besides Aeroquip? Bill B --part1_4d0c4.5d1d8727.3e8f567f_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
Cranking amps may exceed 110. If a bulkhead fitting is used yo= u=20 might well be using the hose as a parallel path with your ground strap. Thi= s is=20 more than enough current to weld steel tubing. If one start were attempted = with=20 the ground strap loose you have used the braid as your ground. In the racer= the=20 battery ground strap bolts on with one of the starter bolts. The matin= g=20 surfaces between the starter and the engine must be free of dirt and paint.= =20
 
Most people choose the Teflon lined hose assemblies for weight= =20 savings. Both Aeroquip and others have Nitrile liners and double stainless= =20 braid. Even a cloth cover so as not to saw through an important part or oth= er=20 hoses. Also the SAE specs  have similar hoses at far lower cost. = You=20 must maintain similar fittings as one is a 45 degree fitting and the other = is a=20 30 degree. Any hose shop can set you up with swaged hose ends and test them= to=20 1,000 PSI if you like. The stainless braid looks racy but you see very litt= le of=20 it on real airplanes. 
 
Lynn E. Hanover  
 
In a message dated 4/4/2013 4:45:18 P.M. Eastern Daylight Time,=20 bbradburry@bellsouth.net writes:
=

Good points al= l,=20 Rich.

 

I am basically= doing=20 the conditional now.  I have the cowl off and am only running the en= gine=20 to improve the tuning.  That is why I was inquiring about recommenda= tions=20 for fuel hose.  With the cowl off, there is a fairly stiff breeze th= at=20 carries away any fuel vapor.  I do suspect that there was some kind = of=20 path of least resistance that caused this problem originally.  I now= have=20 two #4 welding cables attached from each battery to each side of the star= ter=20 which is mounted on the PSRU plate.  During this conditional, I plan= to=20 attach about a 12 ga wire from the center iron to each battery just in ca= se=20 the ignition ground is looking for a better path due to the sandwich you= =20 mention.

 

Bill=20 B

From:=20 Rotary motors in aircraft=20 [mailto:flyrotary@lancaironline.net] On=20 Behalf Of ARGOLDMAN@aol.com
Sent: Thursday, April 04, 2013 4:2= 2=20 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Replaceme= nt for=20 Aeroquip fuel hose

 

Bill,=20

 

This probably= goes=20 without saying, but it is vital to determine why the arcing is happening.= this=20 may be a tremendous safety issue for you (and others)=20

 

Arching does = not=20 happen in a vacuum (actually it is easier there) but there is a reason. I= t is=20 possible that your electrical system is using your FUEL lines ( spelled l= ines=20 full of FUEL) for the grounding of somewhat high amperage loads, such as= =20 starter or alternator.

 

One thing to= =20 ascertain is " is your engine adequately grounded". The engine mount is a= poor=20 conductor. you need a good grounding strap (line) between the "-" of your= =20 battery and the case of the engine. Since our engines are sandwiches and = there=20 is a possibility (possibly remote) that there is some resistance between = the=20 bread and the meat, your current, wanting the path of least resistance ma= y be=20 using those fuel lines. Perhaps you need a better ground to the mounting = bolts=20 of your starter and/or alternator.

 

I donnknow, i= f it=20 were me, I would do the fuel line inspection, correction and=20 replacement=20 NOW, before furt= her=20 starting of the engine.

 

By the way, w= hat is=20 your rationale for delaying until the next conditional to correct a probl= em=20 where there may be significant current flowing through your fuel lines,= =20 especially when there is a fuel smell. You don't smell liquid fuel, you s= mell=20 the vapor. Lessee vapor mixed with fuel in the proper proportions with=20 some sort of ignition system --lets say an electric shock-- may make= your=20 next conditional inspection unnecessary.

 

Keep safe and= fly=20 safely

 

Rich

 

In a message = dated=20 4/4/2013 3:01:53 P.M. Central Daylight Time, bbradburry@bellsouth.net=20 writes:

I have sever= al=20 black spots on the SS braid for my fuel hoses they look like they were= =20 caused by an electrical arc?  I think I can smell fuel around the= =20 spots.  I plan to replace them at the conditional this month. = ;=20 What fuel hoses are being used besides=20 Aeroquip?

 <= /o:p>

Bill=20 B

<= /DIV> --part1_4d0c4.5d1d8727.3e8f567f_boundary--