X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from outbound-mail.vgs.untd.com ([64.136.55.15] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with SMTP id 5095225 for flyrotary@lancaironline.net; Wed, 17 Aug 2011 12:44:17 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.136.55.15; envelope-from=alwick@juno.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=juno.com; s=alpha; t=1313599421; bh=47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=; l=0; h=Message-ID:From:To:Subject:Date:Content-Type; b=M1wJGBWyLWCbowNtUMUriOWJWN4mdRPnd8DQspVftXX8eTgTRq94rnKd5M+UnPuSv k0qHW05gzS0KXpV1gwZkKtK54Jj3B4zBB3XjIN7c9dBMbLAY3CTcw3IdbPzuCXzTxB cCCx/YHAoqhMXAbl4Mt5jfU9YeXsiywL56BiTyj4= Received: from Penny (50-39-174-23.bvtn.or.frontiernet.net [50.39.174.23]) by smtpout05.vgs.untd.com with SMTP id AABHEZ56NAK99KHJ for (sender ); Wed, 17 Aug 2011 09:42:52 -0700 (PDT) Message-ID: From: "Al Wick" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, for that matter. Date: Wed, 17 Aug 2011 09:42:50 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0178_01CC5CC2.0753E050" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Windows Mail 6.0.6002.18197 X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6002.18463 X-UNTD-BodySize: 7090 X-ContentStamp: 17:8:4137416990 X-MAIL-INFO:4d0302430243fbbf43a7fb1fa7fbba6afe1b7f3b8ece237ffe67ae678f33ce6f67fbaf2a1a2a1ade5e1adbde97dbde636f2e2ba73b63831f3fa74b5a7ebbbb77ef9fcf8b2a331a5ff72adb3a3a0ff7dfc34afab75eb76bc73f83ab9a3a8a8b73c75f4f736e87b70f274ea38bce7bdaab4f9eee67fee70aa30a2b1a1b6e47ebce7bbf030302238f67aa1f2f3b X-UNTD-OriginStamp: L941HVjjYzDhN3itp//mkEBOCQjt7GJ/ceq9heB7h9aQpwFu0f6Uxg== X-UNTD-Peer-Info: 10.181.42.35|smtpout05.vgs.untd.com|smtpout05.vgs.untd.com|alwick@juno.com This is a multi-part message in MIME format. ------=_NextPart_000_0178_01CC5CC2.0753E050 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable < I had the issue of a the pressurized lines being=20 < perfectly sealed.=20 So, in the future, if you have a bad injector you don't want to know = about it? I'd want to be able to smell that fuel leak and replace the = defective injector. I would not want to mask it.=20 -al wick ----- Original Message -----=20 From: Ernest Christley=20 To: Rotary motors in aircraft=20 Sent: Wednesday, August 17, 2011 8:22 AM Subject: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, = for that matter. Al Wick wrote: > I'm really concerned for some of these fuel designs. The fuel bleed = has=20 > nothing to do with vapor lock. Virtually no effect at all. > =20 I don't know why others are doing it, but for me, the bleed has = nothing at all to do with vapor lock. Some=20 conversations have been mixed together, so I can see how that could be = the impression. The point of the pressure bleed=20 is to bleed off the pressure after shutdown. I have a strong, positive head pressure going into my pumps. They, = and the regulator, are about 8" directly below the=20 tank. Excess fuel goes back to the opposite side of the tank from the = pickup, and a single line goes forward to feed=20 the injectors. The fuel lines are arranged such that heat soaking the = lines to the point of boiling the gas will push=20 liquid fuel down hill and behind the firewall, isolating the gaseous = gas with its heat at the top of the line. Turning=20 the pumps on will pressurize the line to 55psi, returning most of the = gaseous fuel back to a liquid state. The ECM is=20 programmed for a longer clearing pulse on hot start. The point of the bleed is to allow fuel to move back to the tank. I = had the issue of a the pressurized lines being=20 perfectly sealed. The pressurized fuel was finding the path of least = resistance out, which just happened to be out the=20 injector and into the intake manifold where it sat as a little puddle. = Heat soaking the lines would not push liquid=20 fuel downhill and back behind the firewall. It would push more fuel = into the manifold. A puddle of gas sitting in a=20 composite manifold, just above a hot exhaust stack is just bad mojo. = A poorly sealed regulator allows the pressure to=20 bleed off in about 5 seconds (give or take), isolating the hot fuel in = front of the firewall, and keeping the rest cool=20 and out of the intake manifold. Got nuthin' to do with vapor lock. -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html ------=_NextPart_000_0178_01CC5CC2.0753E050 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
< I had the issue of a the pressurized lines being=20
  < perfectly sealed.
 
So, in the future, if you have a bad = injector you=20 don't want to know about it? I'd want to be able to smell that fuel leak = and=20 replace the defective injector. I would not want to mask it. =
 
-al wick
----- Original Message -----
From:=20 Ernest=20 Christley
Sent: Wednesday, August 17, = 2011 8:22=20 AM
Subject: [FlyRotary] Re: Dennis = Haverlah=20 Fuel System...or any others, for that matter.

Al Wick wrote:
> I'm really concerned for some of = these=20 fuel designs. The fuel bleed has
> nothing to do with vapor = lock.=20 Virtually no effect at all.
> 

I don't know why = others are=20 doing it, but for me, the bleed has nothing at all to do with vapor=20 lock.  Some
conversations have been mixed together, so I can = see how=20 that could be the impression.  The point of the pressure bleed =
is to=20 bleed off the pressure after shutdown.

I have a strong, = positive head=20 pressure going into my pumps.  They, and the regulator, are about = 8"=20 directly below the
tank.  Excess fuel goes back to the = opposite side=20 of the tank from the pickup, and a single line goes forward to feed =
the=20 injectors.  The fuel lines are arranged such that heat soaking = the lines=20 to the point of boiling the gas will push
liquid fuel down hill = and behind=20 the firewall, isolating the gaseous gas with its heat at the top of = the=20 line.  Turning
the pumps on will pressurize the line to = 55psi,=20 returning most of the gaseous fuel back to a liquid state.  The = ECM is=20
programmed for a longer clearing pulse on hot start.

The = point of=20 the bleed is to allow fuel to move back to the tank.  I had the = issue of=20 a the pressurized lines being
perfectly sealed.  The = pressurized fuel=20 was finding the path of least resistance out, which just happened to = be out=20 the
injector and into the intake manifold where it sat as a little = puddle.  Heat soaking the lines would not push liquid
fuel = downhill=20 and back behind the firewall.  It would push more fuel into the=20 manifold.  A puddle of gas sitting in a
composite manifold, = just=20 above a hot exhaust stack is just bad mojo.  A poorly sealed = regulator=20 allows the pressure to
bleed off in about 5 seconds (give or = take),=20 isolating the hot fuel in front of the firewall, and keeping the rest = cool=20
and out of the intake manifold.

Got nuthin' to do with = vapor=20 lock.

--
Homepage:  http://www.flyrotary.com/
Archi= ve and=20 UnSub:   http:= //mail.lancaironline.net:81/lists/flyrotary/List.html
------=_NextPart_000_0178_01CC5CC2.0753E050--