X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-da04.mx.aol.com ([205.188.105.146] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTP id 5095208 for flyrotary@lancaironline.net; Wed, 17 Aug 2011 12:31:16 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.105.146; envelope-from=lehanover@aol.com Received: from mtaomg-db02.r1000.mx.aol.com (mtaomg-db02.r1000.mx.aol.com [172.29.51.200]) by imr-da04.mx.aol.com (8.14.1/8.14.1) with ESMTP id p7HGUD5s023405 for ; Wed, 17 Aug 2011 12:30:13 -0400 Received: from core-mob005b.r1000.mail.aol.com (core-mob005.r1000.mail.aol.com [172.29.194.209]) by mtaomg-db02.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id D2094E00008A for ; Wed, 17 Aug 2011 12:30:12 -0400 (EDT) References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, for that matter. X-AOL-IP: 24.253.65.97 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: lehanover@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CE2B1212880908_1738_4262D_webmail-m071.sysops.aol.com" X-Mailer: AOL Webmail 34047-STANDARD Received: from 24.253.65.97 by webmail-m071.sysops.aol.com (64.12.141.17) with HTTP (WebMailUI); Wed, 17 Aug 2011 12:30:12 -0400 Message-Id: <8CE2B12127C2223-1738-1431D@webmail-m071.sysops.aol.com> X-Originating-IP: [24.253.65.97] Date: Wed, 17 Aug 2011 12:30:12 -0400 (EDT) x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:329893728:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d33c84e4bec94439d This is a multi-part message in MIME format. ----------MB_8CE2B1212880908_1738_4262D_webmail-m071.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="us-ascii" When Mazda put out the early cars RX2 and RX3 they had a return line in the= main fuel line that ran past the carb and back to the tank. This kept the = carb supplied with the coolest fuel in any condition. The actual fuel press= ure was about a pound. Worked great. Until you raced the car then the 2 pie= ce spring loaded needle would let the engine flood when the car was side lo= aded.=20 Radiant energy from all of the exhaust system can heat anything it can "SEE= ". Any straight line from any exhaust piece to anything you wanted kept cool will defeat you. It is easier to shield the exhaust parts than d= oing everything else. An air supply to the exhaust shielding to urge the he= at out of the cowl is all that is left. Mr, Murphy, my science teacher had = a glass water jug he had removed most of the air from, but left behind abou= t 3 inches of water. If you held your hands on the sides of the jug, the water would boil. There= is your vapor lock. Heat and low pressure. Presto. Works every time. Pumps= lower than the tank where possible. Fuel and fuel lines as cool as possibl= e.=20 Lynn E. Hanover -----Original Message----- From: Ernest Christley To: Rotary motors in aircraft Sent: Wed, Aug 17, 2011 4:23 am Subject: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, for t= hat 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=20 to do with vapor lock. Some=20 conversations have been mixed together, so I can see how that could be the= =20 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= =20 regulator, are about 8" directly below the=20 tank. Excess fuel goes back to the opposite side of the tank from the pick= up,=20 and a single line goes forward to feed=20 the injectors. The fuel lines are arranged such that heat soaking the line= s to=20 the point of boiling the gas will push=20 liquid fuel down hill and behind the firewall, isolating the gaseous gas wi= th=20 its heat at the top of the line. Turning=20 the pumps on will pressurize the line to 55psi, returning most of the gaseo= us=20 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 th= e=20 issue of a the pressurized lines being=20 perfectly sealed. The pressurized fuel was finding the path of least resis= tance=20 out, which just happened to be out the=20 injector and into the intake manifold where it sat as a little puddle. Hea= t=20 soaking the lines would not push liquid=20 fuel downhill and back behind the firewall. It would push more fuel into t= he=20 manifold. A puddle of gas sitting in a=20 composite manifold, just above a hot exhaust stack is just bad mojo. A poo= rly=20 sealed regulator allows the pressure to=20 bleed off in about 5 seconds (give or take), isolating the hot fuel in fron= t of=20 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 =20 ----------MB_8CE2B1212880908_1738_4262D_webmail-m071.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="us-ascii" When Mazda put out the early ca= rs RX2 and RX3 they had a return line in the main fuel line that ran past t= he carb and back to the tank. This kept the carb supplied with the coolest = fuel in any condition. The actual fuel pressure was about a pound. Worked g= reat. Until you raced the car then the 2 piece spring loaded needle would l= et the engine flood when the car was side loaded. 

Radiant energy from all of the exhaust system can heat anything it can "SE= E". Any straight line from any exhaust piece to anything you  wanted
 kept cool will defeat you. It is easier to shield the exhaust parts = than doing everything else. An air supply to the exhaust shielding to urge = the heat out of the cowl is all that is left. Mr, Murphy, my science teache= r had a glass water jug he had removed most of the air from, but left behin= d about 3 inches of water.

If you held your hands on the sides of the jug, the water would boil. Ther= e is your vapor lock. Heat and low pressure. Presto. Works every time. Pump= s lower than the tank where possible. Fuel and fuel lines as cool as possib= le. 

Lynn E. Hanover



-----= Original Message-----
From: Ernest Christley <echristley@att.net>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, Aug 17, 2011 4:23 am
Subject: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, for t= hat matter.

Al Wick wrote:
> I'm really concerned for some of these fuel designs. The fuel bleed ha=
s=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=20
to do with vapor lock.  Some=20
conversations have been mixed together, so I can see how that could be the=
=20
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=
=20
regulator, are about 8" directly below the=20
tank.  Excess fuel goes back to the opposite side of the tank from the pick=
up,=20
and a single line goes forward to feed=20
the injectors.  The fuel lines are arranged such that heat soaking the line=
s to=20
the point of boiling the gas will push=20
liquid fuel down hill and behind the firewall, isolating the gaseous gas wi=
th=20
its heat at the top of the line.  Turning=20
the pumps on will pressurize the line to 55psi, returning most of the gaseo=
us=20
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 th=
e=20
issue of a the pressurized lines being=20
perfectly sealed.  The pressurized fuel was finding the path of least resis=
tance=20
out, which just happened to be out the=20
injector and into the intake manifold where it sat as a little puddle.  Hea=
t=20
soaking the lines would not push liquid=20
fuel downhill and back behind the firewall.  It would push more fuel into t=
he=20
manifold.  A puddle of gas sitting in a=20
composite manifold, just above a hot exhaust stack is just bad mojo.  A poo=
rly=20
sealed regulator allows the pressure to=20
bleed off in about 5 seconds (give or take), isolating the hot fuel in fron=
t of=20
the firewall, and keeping the rest cool=20
and out of the intake manifold.

Got nuthin' to do with vapor lock.

--
Homepage:  http://w=
ww.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/f=
lyrotary/List.html
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