Return-Path: Received: from [216.52.245.18] (HELO ispwestemail2.mdeinc.com) by logan.com (CommuniGate Pro SMTP 4.3c2) with ESMTP id 759064 for flyrotary@lancaironline.net; Fri, 25 Feb 2005 11:06:56 -0500 Received-SPF: none receiver=logan.com; client-ip=216.52.245.18; envelope-from=wschertz@ispwest.com Received: from 7n7z201 (unverified [67.136.146.22]) by ispwestemail2.mdeinc.com (Vircom SMTPRS 4.0.340.3) with SMTP id for ; Fri, 25 Feb 2005 08:05:58 -0800 Message-ID: <01c501c51b53$e44f87a0$16928843@7n7z201> From: "William" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Vapor Lock Date: Fri, 25 Feb 2005 09:54:51 -0600 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0150_01C51B20.0C9F5840" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_0150_01C51B20.0C9F5840 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable There is another phenomina that exists that would be very subtle. People = can design fluid flow 'flip-flop' circuits, that will take two streams = that merge into one outlet, and can make them draw from either side with = the momentary application of a side pressure. Once started, the flow = continues from the given side until it is purposely reversed. I can = envision (but don't know how to design) a situation where there is a = subtle difference that encourages that behavior. Bill Schertz KIS Cruiser # 4045 ----- Original Message -----=20 From: Jim Sower=20 To: Rotary motors in aircraft=20 Sent: Thursday, February 24, 2005 9:35 PM Subject: [FlyRotary] Re: Vapor Lock Paul, Paul wrote: Hi, Jim....is it possible there is a restriction in one of the fuel = lines? Are there any bends in the aluminum fuel line that might have = kinked during the bending process?=20 This problem drove me NUTS for two years. I tried everything. For = example, I checked the vents as best I could, leveled the airplane = (checked the ball to ensure it was centered - it was), disconnected the = fuel line from the engine side of the firewall and let it drain into a = bucket. I turned off one strake at a time (with manual maintenance = valve) and timed how long it took for the other strake to gravity drain = ten gal of fuel into the sump, out of the sump through the boost pump, = through the filter and then through the firewall into the bucket(s). = Then I turned it off and did the same thing with the left tank. They = both drained 10 gal each within 5% of the same time. Then I = reconnected all the plumbing, taped over the fuel caps so there's no = possible way they could leak and went flying. Right tank drained 20 gal = while the left tank maybe 2 or 3. Level balanced flight on a cross = country. All fuel lines, vent lines, etc. are as identical as I am able = to make them. To this day, I've not met anybody who can explain what = happened. I tried everything. Back and forth on the Velocity list much = longer than you've been inquiring after your vapor lock. NOTHING. I = figured out a workaround - I installed electric shutoff valves in place = of the manual maintenance valves between the strake and the sump. Now, = when one tank doesn't transfer, I turn off the tank that does and let = the "reluctant" tank catch up. The pump sucks it through the system = just fine (the head pressure of 6" of fuel is about 0.16 psi - a problem = that would inhibit that flow you can't even MEASURE. Assymmetric = transfer is common as dirt in the Velocity community (but not nearly as = persistent as mine). It was also a problem a long time with the = Vari-EZ. Lastly, have you tried blowing backwards into the two fuel lines to = see if either had more restriction than the other? Just looking for = possible reasons for your uneven fuel flow. Even my Cessna 172 and 150 = had fairly even fuel consumption from the two gravity fed tanks.=20 I understand that Cessnas had a lot of trouble around this too. Just searching for answers. Paul Conner=20 ----- Original Message ----- From: "Jim Sower" = =20 To: "Rotary motors in aircraft" =20 Sent: Thursday, February 24, 2005 5:57 PM=20 Subject: [FlyRotary] Re: Vapor Lock=20 In my Velocity the strakes gravity feed to the sump. About a foot = of 3/8" Al / rubber fuel line on each side, downhill all the way. I can = run one tank plumb dry and have only a gallon or two gone out of the = other. Like when there's a slight leak in a fuel cap or something.=20 If they're significantly uneven, you WILL get air if you select = "Both" ... Jim S.=20 Bulent Aliev wrote:=20 If you're almost home and have "Both" selected, and = one=20 tank runs dry, what do you end up with in the fuel = line? I=20 believe mostly air. Late in the trip (traffic = pattern?)=20 where trouble shooting time is at a premium. Use L = or R.=20 Not B.=20 I don=92t think so: connect two tanks (one full with water and = one empty) to gravity feed Into Y connection. Than suck on the end and = try to breathe. Let me know how it works :)=20 Buly=20 Homepage: http://www.flyrotary.com/=20 Archive: http://lancaironline.net/lists/flyrotary/List.html = --=20 No virus found in this incoming message.=20 Checked by AVG Anti-Virus.=20 Version: 7.0.300 / Virus Database: 266.4.0 - Release Date: = 2/22/2005=20 >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_0150_01C51B20.0C9F5840 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
There is another phenomina that exists = that would=20 be very subtle. People can design fluid flow 'flip-flop' circuits, that = will=20 take two streams that merge into one outlet, and can make them draw from = either=20 side with the momentary application of a side pressure. Once started, = the flow=20 continues from the given side until it is purposely reversed. I can = envision=20 (but don't know how to design) a situation where there is a subtle = difference=20 that encourages that behavior.
 
Bill Schertz
KIS Cruiser # 4045
----- Original Message -----
From:=20 Jim=20 Sower
Sent: Thursday, February 24, = 2005 9:35=20 PM
Subject: [FlyRotary] Re: Vapor = Lock

Paul,
Paul wrote:
Hi, = Jim....is it=20 possible there is a restriction in one of the fuel lines? Are there = any=20 bends in the aluminum fuel line that might have kinked during the = bending=20 process?
This problem drove = me NUTS for=20 two years.  I tried everything.  For example, I checked the = vents as=20 best I could, leveled the airplane (checked the ball to ensure it was = centered=20 - it was), disconnected the fuel line from the engine side of the = firewall and=20 let it drain into a bucket.  I turned off one strake at a time = (with=20 manual maintenance valve) and timed how long it took for the other = strake to=20 gravity drain ten gal of fuel into the sump, out of the sump through = the boost=20 pump, through the filter and then through the firewall into the=20 bucket(s).  Then I turned it off and did the same thing with the = left=20 tank.  They both drained 10 gal each  within 5% of the same=20 time.  Then I reconnected all the plumbing, taped over the fuel = caps so=20 there's no possible way they could leak and went flying.  Right = tank=20 drained 20 gal while the left tank maybe 2 or 3.  Level balanced = flight=20 on a cross country.  All fuel lines, vent lines, etc. are as = identical as=20 I am able to make them.  To this day, I've not met anybody = who can=20 explain what happened.  I tried everything.  Back and = forth=20 on the Velocity list much longer than you've been inquiring after your = vapor=20 lock.  NOTHING.  I figured out a workaround - I installed = electric=20 shutoff valves in place of the manual maintenance valves between the = strake=20 and the sump.  Now, when one tank doesn't transfer, I turn off = the tank=20 that does and let the "reluctant" tank catch up.  The pump sucks = it=20 through the system just fine (the head pressure of 6" of fuel is about = 0.16=20 psi - a problem that would inhibit that flow you can't even = MEASURE. =20 Assymmetric transfer is common as dirt in the Velocity community (but = not=20 nearly as persistent as mine).  It was also a problem a long time = with=20 the Vari-EZ.
Lastly, have = you tried=20 blowing backwards into the two fuel lines to see if either had more=20 restriction than the other?  Just looking for possible reasons = for your=20 uneven fuel flow.  Even my Cessna 172 and 150 had fairly even = fuel=20 consumption from the two gravity fed tanks.
I understand that Cessnas had a lot of trouble around = this=20 too.
Just = searching for=20 answers.  Paul Conner

----- Original Message ----- = From: "Jim=20 Sower" <canarder@frontiernet.net>= =20
To: "Rotary motors in aircraft" <flyrotary@lancaironline.n= et>=20
Sent: Thursday, February 24, 2005 5:57 PM
Subject: = [FlyRotary] Re:=20 Vapor Lock


In my Velocity the strakes gravity feed to = the=20 sump. About a foot of 3/8" Al / rubber fuel line on each side, = downhill=20 all the way. I can run one tank plumb dry and have only a gallon = or two=20 gone out of the other. Like when there's a slight leak in a fuel = cap or=20 something.
If they're significantly uneven, you WILL get air = if you=20 select "Both" ... Jim S.

Bulent Aliev wrote:



        &nb= sp;  =20 If you're almost home and have "Both" selected, and one=20 =
           =20 tank runs dry, what do you end up with in the fuel line? I=20 =
           =20 believe mostly air. Late in the trip (traffic pattern?)=20 =
           =20 where trouble shooting time is at a premium. Use L or R.=20 =
           =20 Not B.

I don=92t think so: connect two tanks (one full = with water=20 and one empty) to gravity feed Into Y connection. Than suck on = the end=20 and try to breathe. Let me know how it works :)
Buly=20


 Homepage:  http://www.flyrotary.com/=20
 Archive:   http://lancai= ronline.net/lists/flyrotary/List.html=20


-- 
No virus = found in this=20 incoming message.
Checked by AVG Anti-Virus.
Version: = 7.0.300 /=20 Virus Database: 266.4.0 - Release Date: 2/22/2005=20 






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