X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imf20aec.mail.bellsouth.net ([205.152.59.68] verified) by logan.com (CommuniGate Pro SMTP 5.1c.2) with ESMTP id 1330597 for flyrotary@lancaironline.net; Mon, 31 Jul 2006 15:57:17 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.68; envelope-from=brecab@bellsouth.net Received: from ibm64aec.bellsouth.net ([68.18.117.61]) by imf20aec.mail.bellsouth.net with ESMTP id <20060731195620.VKNZ10418.imf20aec.mail.bellsouth.net@ibm64aec.bellsouth.net> for ; Mon, 31 Jul 2006 15:56:20 -0400 Received: from 1dd8d01.bellsouth.net ([68.18.117.61]) by ibm64aec.bellsouth.net with ESMTP id <20060731195618.JRAE12906.ibm64aec.bellsouth.net@1dd8d01.bellsouth.net> for ; Mon, 31 Jul 2006 15:56:18 -0400 Message-Id: <7.0.1.0.1.20060731154557.0232bb58@bellsouth.net> X-Mailer: QUALCOMM Windows Eudora Version 7.0.1.0 Date: Mon, 31 Jul 2006 15:57:03 -0400 To: "Rotary motors in aircraft" From: CCI Subject: Re: [FlyRotary] Auto Fuel - composite tanks In-Reply-To: References: Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="=====================_32884845==.ALT" --=====================_32884845==.ALT Content-Type: text/plain; charset="iso-8859-1"; format=flowed Content-Transfer-Encoding: quoted-printable Hi Al, I don't know if this has any relevance to=20 your problem or not, but about a year ago some=20 fuel that came from the Thorton chain around our=20 area was eating up fuel senders. Several people I=20 know had this problem, Thorton's took care of=20 replacing I don't know how many senders. What I=20 heard was there was an extremly high sulphur=20 content in the fuel that was attacking the=20 senders. I don't know if this is related to your=20 problem or not, but I would drain the fuel and=20 see if someone in your area might be able to test=20 a sample of it to see what it has in it. Fred At 10:14 AM 7/31/2006 -0700, you wrote: >Not sure where to go with this because there are=20 >only a few here with epoxy fuel tanks, and on=20 >the Velocity list very few interested in the use=20 >of mogas. I=92m suspecting fuel compatibility isses. > >I first put fuel in the tanks nearly 2 years ago=20 >and used Chevron regular. Everything was=20 >fine. When I moved the plane to the airport 3=20 >months ago (tanks empty) I filled with=20 >Exxon-Mobile. Four troubling things have come up in the past few weeks. > > * I have Vance Atkinson site gauge that has=20 > a white plastic back plate for easier reading=20 > of the fuel level. The small hole through the=20 > backing has been swelling shut so the sight=20 > gauge no longer works. I contacted Vance who=20 > said that there are hundreds of these gauges in=20 > EZs using mogas without problems, but he has=20 > had 3 incidents like mine in the last three months. > * A couple of weeks ago there was suddenly a=20 > pinhole leak in one of the gear well=20 > enclosures. These enclosures are part of the=20 > fuel tank wall, and are parts that come with=20 > the Velocity kit. These are also made and coated with EZ-poxy. > * Looking in through the filler cap I see=20 > reddish-purple splotches and streaks on those=20 > gear leg enclosures. Poking and scratching=20 > with some safety wire on a stick does not=20 > indicate any softness of the surface. > * Yesterday, under the leading edges of one=20 > of the strakes, I noted an area with some=20 > slight surface irregularity. Pushing on it=20 > suggests some sponginess. This is =BD=94 foam core=20 > material, and indicates the possibility of a=20 > pinhole leak in the inner skin, and fuel=20 > softening the PVC foam. PVC foam is supposed to be unaffected by fuel. > >My tanks (strakes) were made and coated with=20 >EZ-poxy back in 1998. At the time I polled EZ=20 >flyers about there experience, and talked to=20 >reps of various epoxy manufacturers about auto=20 >fuel compatibility. All the evidence said go with the EZ-poxy. > >Any others with composite tanks having any=20 >trouble? Anybody using Exxon-mobile fuel? Know=20 >of any new additives that are an issue? > >I=92m thinking I should drain this fuel ASAP, but=20 >then what? Other brand? That expensive=20 >Avgas? Regardless I may be faced with cutting=20 >open a strake at some point, but right now we=20 >are trying to get first flight done this coming weekend. > > --=====================_32884845==.ALT Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Al, I don't know if this has any relevance to your problem or not, but about a year ago some fuel that came from the Thorton chain around our area was eating up fuel senders. Several people I know had this problem, Thorton's took care of replacing I don't know how many senders. What I heard was there was an extremly high sulphur content in the fuel that was attacking the senders. I don't know if this is related to your problem or not, but I would drain the fuel and see if someone in your area might be able to test a sample of it to see what it has in it.  Fred



At 10:14 AM 7/31/2006 -0700, you wrote:
Not sure where to go with this because there are only a few here with epoxy fuel tanks, and on the Velocity list very few interested in the use of mogas.  I=92m suspecting fuel compatibility isses.
 
I first put fuel in the tanks nearly 2 years ago and used Chevron regular. Everything was fine.  When I moved the plane to the airport 3 months ago (tanks empty) I filled with Exxon-Mobile.  Four troubling things have come up in the past few weeks.
 
  1. I have Vance Atkinson site gauge that has a white plastic back plate for easier reading of the fuel level. The small hole through the backing has been swelling shut so the sight gauge no longer works. I contacted Vance who said that there are hundreds of these gauges in EZs using mogas without problems, but he has had 3 incidents like mine in the last three months.=20
  2. A couple of weeks ago there was suddenly a pinhole leak in one of the gear well enclosures.  These enclosures are part of the fuel tank wall, and are parts that come with the Velocity kit.  These are also made and coated with EZ-poxy.=20
  3. Looking in through the filler cap I see reddish-purple splotches and streaks on those gear leg enclosures.  Poking and scratching with some safety wire on a stick does not indicate any softness of the surface.=20
  4. Yesterday, under the leading edges of on= e of the strakes, I noted an area with some slight surface irregularity.  Pushing on it suggests some sponginess.  This is =BD=94 foam core material, and indicates the possibility of a pinhole leak i= n the inner skin, and fuel softening the PVC foam.  PVC foam is supposed to be unaffected by fuel.=20
 
My tanks (strakes) were made and coated with EZ-poxy back in 1998.  At the time I polled EZ flyers about there experience, and talked to reps of various epoxy manufacturers about auto fuel compatibility.  All the evidence said go with the EZ-poxy.
 
Any others with composite tanks having any trouble?  Anybody using Exxon-mobile fuel?  Know of any new additives that are an issue?
 
I=92m thinking I should drain this fuel ASAP, but then what?  Other brand?  That expensive Avgas?  Regardless I may be faced with cutting open a strake at some point, but right now we are trying to get first flight done this coming weekend.
 
 

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