X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from qw-out-2122.google.com ([74.125.92.24] verified) by logan.com (CommuniGate Pro SMTP 5.2.12) with ESMTP id 3519309 for flyrotary@lancaironline.net; Fri, 27 Feb 2009 10:43:42 -0500 Received-SPF: pass receiver=logan.com; client-ip=74.125.92.24; envelope-from=rwstracy@gmail.com Received: by qw-out-2122.google.com with SMTP id 8so1082646qwh.25 for ; Fri, 27 Feb 2009 07:43:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type; bh=4VPcMzPKqGuGMobaxlVdJh6sGUrDbtwTnVbj05CH7Dw=; b=hEJD6a63FOtS72bDMAHSTqcaDElKm1ks57G6ozmg+BI3JpatIVh0S/eEwp29ldAjy9 6OsJeS3WzwofrGBEsjcUp3Ypv9bQkseLHEZbkCWr4cxfY0e2yJ925QExTOlgVVHzX26m H78+wcDP1HUfwqMo16he8lPVtm6l7HzDBG3jE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=PKye5wgf+TFo2Q8kuhMA+RsPtZPjJJ6E4zfA5yGvLy4uYpDhmKPbriREwfqCSKlnI/ HohlC8zE2gVqdYFXHNLOLqR3ADBHO3Bo2a/tOZzLRzy8FIdLdXq9EjEkesXZP9ilOFkE PxbieuICGsvOlwWX+ITMY6rF0uDGhzTCVSdJk= MIME-Version: 1.0 Sender: rwstracy@gmail.com Received: by 10.224.28.207 with SMTP id n15mr4293625qac.91.1235749387944; Fri, 27 Feb 2009 07:43:07 -0800 (PST) In-Reply-To: References: Date: Fri, 27 Feb 2009 10:43:07 -0500 X-Google-Sender-Auth: 11ea54014c4c5347 Message-ID: <1b4b137c0902270743r5d1c92f9t32636ec059ec348b@mail.gmail.com> Subject: Re: [FlyRotary] ethanol From: Tracy Crook To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=0015175cb5564cc4470463e85362 --0015175cb5564cc4470463e85362 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit FWIW, Possible source of the 'black flakes' is fuel pump impeller pieces. When these pumps run dry their lifetime is measured in minutes. The impellers will abraid and shed small pieces. Insure that the path from tank to pump is down hill or at least level with the fuel and there are no restrictive filters or other obstacles in this path. I don't even like to see boost pumps there because there is a significant drop in pressure across their check valves. Tracy On Thu, Feb 26, 2009 at 10:59 PM, Mike Wills wrote: > Well things seem a little slow today so how about re-opening a can of > worms? We had a brief discussion a while back regarding ethanol in fuel. > Frankly at the time I didnt know much about the subject but have been > reading a little since I'm burning auto fuel. > > At the time I think it was Al G. who said so far he hasnt found any auto > fuel with ethanol in it. If I got that wrong I apologize. So far I havent > found any auto fuel that DOESNT. As far as I can tell from my reading ALL > auto fuel in CA has at least 6% and most is at 10% now. > > Looks like the concerns are: > 1) Vapor lock > 2) Potential corrosion of aluminum components in the fuel system. > 3) Deterioration of rubber (and other?) components in the fuel system. > 4) Water. > 5) Dislodging contaminants from previously used fuels. > > I believe (hope?) the vapor lock issues to be a non-problem with our EFI > systems. The potential corrosion issues seem to be overstated for ethanol, > clearly a problem with methanol. All the hose in my airplane is Earls > Perform-O-Flex which according to their website is "synthetic rubber". I > assume they mean neoprene which I gather is ethanol safe. I assume the > injectors themselves are safe? I thought Pro-Seal is also supposed to be > ethanol safe. My airplane is new so there should be no issue with dislodged > contaminants. > > This leaves the issue of ethanol's affinity for water. Other than always > keeping the tanks full to minimize airspace in the tank and condensation any > ideas on how to deal with this other than hoping it doesnt happen? > > I bring this subject up because for the second time since I've started > flying I've found a little contamination during my pre-flight when sumping > the tanks. Each fuel sample has a few ground pepper sized black flakes in > it. Whatever it is it crumbles to powder between the fingers. The first > time I completely drained the tanks and pulled the fuel filters and cleaned > them. When I refilled the tanks I used a Mr. Funnel to make sure nothing bad > got added. So whatever this is, its residual junk in the tanks from when > they were built. Or its something (like ethanol) attacking the Pro Seal. > > Any comments on ethanol in general or my fuel contamination issue are > welcome. > > Mike Wills > RV-4 N144MW > --0015175cb5564cc4470463e85362 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable FWIW,
Possible source of the 'black flakes'=A0 is fuel pump impe= ller pieces.=A0 When these pumps run dry their lifetime is measured in minu= tes.=A0 The impellers will abraid and shed small pieces.=A0 Insure that the= path from tank to pump is down hill or at least level with the fuel and th= ere are no restrictive filters or other obstacles in this path.=A0 I don= 9;t even like to see boost pumps there because there is a significant drop = in pressure across their check valves.

Tracy


On Thu, Feb 26, 2009 at 10:= 59 PM, Mike Wills <rv-4mike@cox.net> wrote:
Well things seem a little slow today s= o how about=20 re-opening a can of worms? We had a brief discussion a while back regarding= =20 ethanol in fuel. Frankly at the time I didnt know much about the subject bu= t=20 have been reading a little since I'm burning auto fuel.
=A0
At the time I think it was Al G. who s= aid so far he=20 hasnt found any auto fuel with ethanol in it. If I got that wrong I apologi= ze.=20 So far I havent found any auto fuel that DOESNT. As far as I can tell from = my=20 reading ALL auto fuel in CA has at least 6% and most is at 10% now.<= /div>
=A0
Looks like the concerns are:
1) Vapor lock
2) Potential corrosion of aluminum com= ponents in=20 the fuel system.
3) Deterioration of rubber (and other?= ) components=20 in the fuel system.
4) Water.
5) Dislodging contaminants from previo= usly used=20 fuels.
=A0
I believe (hope?)=A0the vapor lock iss= ues to be=20 a non-problem with our EFI systems. The potential corrosion issues=A0seem t= o=20 be overstated for ethanol, clearly a problem with methanol. All the hose in= my=20 airplane is Earls Perform-O-Flex which according to their website is "= synthetic=20 rubber". I assume they mean neoprene which I gather is ethanol safe. I= assume=20 the injectors themselves are safe?=A0I thought=A0Pro-Seal is also supposed= =20 to be ethanol safe. My airplane is new so there should be no issue with=20 dislodged contaminants.
=A0
This leaves the issue of ethanol's= affinity for=20 water. Other than always keeping the tanks full to minimize airspace in the= tank=20 and condensation any ideas on how to deal with this other than hoping it do= esnt=20 happen?
=A0
I bring this subject up because for th= e second time=20 since I've started flying I've found a little contamination during = my pre-flight=20 when sumping the tanks. Each fuel sample has a few ground pepper sized blac= k=20 flakes in it. Whatever it is it crumbles to powder between the fingers. The= =20 first time=A0I completely drained the tanks and pulled the fuel filters and= =20 cleaned them. When I refilled the tanks I used a Mr. Funnel to make sure no= thing=20 bad got added. So whatever this is, its residual junk in the tanks from whe= n=20 they were built. Or its something (like ethanol) attacking the Pro=20 Seal.
=A0
Any comments on ethanol in general or = my fuel=20 contamination issue are welcome.
=A0
Mike Wills
RV-4 N144MW

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