X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-fx0-f52.google.com ([209.85.161.52] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTPS id 5095594 for flyrotary@lancaironline.net; Wed, 17 Aug 2011 20:58:03 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.52; envelope-from=msteitle@gmail.com Received: by fxd18 with SMTP id 18so975388fxd.25 for ; Wed, 17 Aug 2011 17:57:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=5Rhihmis2V/xMXTOyXIgXgc8kJiH+enfBsmvez4Lc0Q=; b=akwksDtKK7unRZYbyH5+KAquiq1IKt3TI6gETwm+rPKcnI+Wmj1Og8WpIHFkgwQTWW bx/1PBcjB+yBHclTbfVAinCMXY1RO+Z0zJ46PmX7oXkprbziXyJ9uW9di/SRLsaeSA3N S0t4PuGYbHIo1Ave9jJ4HTBhEJalWN6OtSW3g= MIME-Version: 1.0 Received: by 10.223.145.7 with SMTP id b7mr160711fav.56.1313629045391; Wed, 17 Aug 2011 17:57:25 -0700 (PDT) Received: by 10.223.74.129 with HTTP; Wed, 17 Aug 2011 17:57:25 -0700 (PDT) In-Reply-To: References: Date: Wed, 17 Aug 2011 19:57:25 -0500 Message-ID: Subject: Re: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, for that matter. From: Mark Steitle To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=0023545bf3349e025904aabd1883 --0023545bf3349e025904aabd1883 Content-Type: text/plain; charset=ISO-8859-1 Kelly, It is a Holley, model 12-700. Here's a link, http://www.summitracing.com/parts/HLY-12-700/ Its good for 47gph at 80psi. They also make a higher capacity model, p/n 12-890, that is good for 70gph at 80psi. Mark S. On Wed, Aug 17, 2011 at 7:37 PM, Kelly Troyer wrote: > Mark, > What make were the pumps.........The only Gerotor fuel pumps I saw were > Holley > carb pumps (about 15 psi max pressure) ??............... > > Kelly Troyer > *"DYKE DELTA JD2" (Eventually)* > "13B ROTARY"_ Engine > "RWS"_RD1C/EC2/EM2 > "MISTRAL"_Backplate/Oil Manifold > "TURBONETICS"_TO4E50 Turbo > > *From:* Mark Steitle > *To:* Rotary motors in aircraft > *Sent:* Wednesday, August 17, 2011 6:54 PM > *Subject:* [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, > for that matter. > > Tracy, > > What type of pumps are the pumps that you carry, vane? I was looking today > on Summit Racing's site and saw a "gerotor" pump. This is the type pump > Mazda uses for the rotary's oil pump. It was more than twice the price, but > it looks like it would tolerate dry running much better than the vane style > does. So, I'm wondering if this might be a better choice for those that > routinely run their tanks dry before switching to the other tank. I'd hate > to ruin a pump at 14,000msl with lots of fuel in the other tank, but unable > to get it to the injectors. > > Mark S. > > On Wed, Aug 17, 2011 at 5:08 PM, Tracy wrote: > > Just a cautionary note on that testing. If you do the run tank dry test > that Mark suggested, make the 'dry run' portion of the test as short as > possible. Auto mechanics love people to run their tanks dry because it's > good for business. The lifespan of the pump when dry is VERY short. > > Better never to run the tank dry. That was a big reason I used a Facet > transfer pump to the EFI feed tank. You never have to run a tank dry to get > the last drop before running the EFI pump dry. > > Tracy > > On Wed, Aug 17, 2011 at 12:19 PM, Mark Steitle wrote: > > Al, > > I would think that a well-designed fuel system with the pumps located as > low as possible, in a cool area, and a return system should not be troubled > with vapor locking. Although I guess it could happen in Death Valley > in August if the a/c is left out in the sun for 8 hours, and running auto > gas. So far, I haven't had any problem here in Texas (temps 105* today). > > > My purpose for installing the bypass circuit was more critical to safe > flight. (The solution was the result of a forced landing, or two, in an > Eggenfellner Subaru installation.) During ground runs, using a 5-gallon > can, I found that the efi fuel pumps could not restore pressure once the > tank had been allowed to run dry. When this occurred, the EFI pump would > suck a big slug of air into the inlet side of the pump, loose pressure, and > being unable to build psi equal to the pressure regulator setting, it would > stop pumping fuel (vapor lock). The only way to restore operation was to > crack open the system downstream of the pump until the slug of air could be > passed on through the fuel pump. Not sure this meets your definiton of > "vapor lock", but I think it does, but for a different reason than fuel > vapor pressure. > > I have tested this system on the ground and it works as advertized. If the > tank runs dry, switched to a full tank, the efi pump will restore pressure > to the system within a few seconds. I urge all builders to run this test on > their fuel system to determine whether or not their pumps are able to > restore pressure after running a tank dry. Or, just don't ever run a tank > dry. > > Mark S. > > > > On Wed, Aug 17, 2011 at 10:22 AM, Ernest Christley wrote: > > Al Wick wrote: > > I'm really concerned for some of these fuel designs. The fuel bleed has > nothing to do with vapor lock. Virtually no effect at all. > > > > I don't know why others are doing it, but for me, the bleed has nothing at > all to do with vapor lock. Some conversations have been mixed together, so > I can see how that could be the impression. The point of the pressure bleed > 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 tank. Excess fuel goes back to > the opposite side of the tank from the pickup, and a single line goes > forward to feed the injectors. The fuel lines are arranged such that heat > soaking the lines to the point of boiling the gas will push liquid fuel down > hill and behind the firewall, isolating the gaseous gas with its heat at the > top of the line. Turning the pumps on will pressurize the line to 55psi, > returning most of the gaseous fuel back to a liquid state. The ECM is > 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 perfectly sealed. The > pressurized fuel was finding the path of least resistance out, which just > happened to be out the injector and into the intake manifold where it sat as > a little puddle. Heat soaking the lines would not push liquid fuel downhill > and back behind the firewall. It would push more fuel into the manifold. A > puddle of gas sitting in a composite manifold, just above a hot exhaust > stack is just bad mojo. A poorly sealed regulator allows the pressure to > bleed off in about 5 seconds (give or take), isolating the hot fuel in front > of the firewall, and keeping the rest cool 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 > > > > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > --0023545bf3349e025904aabd1883 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Kelly,=A0

It is a Holley, model 12-700. =A0Here's a = link,=A0http://ww= w.summitracing.com/parts/HLY-12-700/ =A0Its good for 47gph at 80psi. = =A0They also make a higher capacity model, p/n 12-890, that is good for 70g= ph at 80psi. =A0=A0

Mark S.

On Wed, Aug 1= 7, 2011 at 7:37 PM, Kelly Troyer <keltro@att.net> wrote:
Mark,
=A0=A0=A0 What make were the pumps.........The only Gerotor fuel= pumps I saw were Holley
carb pumps (about 15 psi max pressure) ??...............
=A0
Kelly Troyer
"DYKE DELTA JD2" = (Eventually)
"13B ROTARY"_ Engine
"RWS"_RD1C/EC2/EM2
&quo= t;MISTRAL"_Backplate/Oil Manifold
"TURBONETICS"_TO4E50 Turbo

From: Mark Steitle <= ;msteitle@gmail.com= >
To: Rotary motor= s in aircraft <flyrotary@lancaironline.net>
Sent: Wednesday, August 17, = 2011 6:54 PM
Subject: [Fl= yRotary] Re: Dennis Haverlah Fuel System...or any others, for that matter.<= br>
Tracy,=A0

What type of pumps are the pumps that you carry, vane? =A0I was lookin= g today on Summit Racing's site and saw a "gerotor" pump. =A0= This is the type pump Mazda uses for the rotary's oil pump. =A0It was m= ore than twice the price, but it looks like it would tolerate dry running m= uch better than the vane style does. =A0So, I'm wondering if this might= be a better choice for those that routinely run their tanks dry before swi= tching to the other tank. =A0I'd hate to ruin a pump at 14,000msl with = lots of fuel in the other tank, but unable to get it to the injectors.

Mark S.

On Wed, Aug 17, 2011 at 5:08 PM, Tracy <rwstracy@= gmail.com> wrote:
Just a cautionary note on that testing.=A0=A0 If you do the= run tank dry test that Mark suggested,=A0 make the 'dry run' porti= on of the test as short as possible. =A0 Auto mechanics love people to run = their tanks dry because it's good for business.=A0 The lifespan of the = pump when dry is VERY short.

Better never to run the tank dry. =A0 That was a big reason I used a Fa= cet transfer pump to the EFI feed tank.=A0 You never have to run a tank dry= to get the last drop before running the EFI pump dry.

Tracy

On Wed, Aug 17, 2011 at 12:19 PM, Mark Steitle <<= a href=3D"mailto:msteitle@gmail.com" rel=3D"nofollow" target=3D"_blank">mst= eitle@gmail.com> wrote:
Al,
=A0
I would think that a well-designed=A0fuel system=A0with the pumps loca= ted as low as possible, in a=A0cool area,=A0and=A0a return system=A0should = not be troubled with vapor locking.=A0=A0Although I guess it could happen i= n Death Valley in=A0August if the a/c is left out in the sun for 8 hours, a= nd running auto gas.=A0 So far, I haven't had any problem here in Texas= (temps 105* today).=A0 =A0
=A0
My purpose for installing the bypass circuit was more critical to safe= flight.=A0 (The solution was=A0the result of a forced landing, or two,=A0i= n an Eggenfellner Subaru installation.)=A0 During ground runs, using a 5-ga= llon can, I found that the efi fuel pumps could not restore pressure once t= he tank had been allowed to run dry.=A0=A0When this occurred, the EFI pump= =A0would suck a big slug of air into the inlet side of the pump, loose pres= sure,=A0and being unable to build psi equal to the pressure regulator setti= ng, it would stop pumping fuel (vapor lock).=A0 The only way to restore ope= ration was to crack open the system downstream of the pump until the slug o= f air could be passed on through the fuel pump.=A0=A0Not sure this meets yo= ur definiton of "vapor lock", but I think it does, but for a diff= erent reason than fuel vapor pressure.
=A0
I have tested this system on the ground and it works as advertized.=A0= If the tank runs dry, switched to a full tank, the efi pump will restore p= ressure to the system within a few seconds.=A0 I urge all builders to run t= his test on their fuel system to determine whether or not their pumps are a= ble to restore pressure after running a tank dry.=A0 Or, just don't eve= r run a tank dry.
=A0
Mark S.


=A0
On Wed, Aug 17, 2011 at 10:22 AM, Ernest Christley &= lt;echristley@att.net> wrote:
Al Wick wrote:
I'm really concerned for some of these fuel designs. Th= e fuel bleed has nothing to do with vapor lock. Virtually no effect at all.=
=A0

I don't know why others are doing it, but= for me, the bleed has nothing at all to do with vapor lock. =A0Some conver= sations have been mixed together, so I can see how that could be the impres= sion. =A0The point of the pressure bleed is to bleed off the pressure after= shutdown.

I have a strong, positive head pressure going into my pumps. =A0They, a= nd the regulator, are about 8" directly below the tank. =A0Excess fuel= goes back to the opposite side of the tank from the pickup, and a single l= ine goes forward to feed the injectors. =A0The fuel lines are arranged such= that heat soaking the lines to the point of boiling the gas will push liqu= id fuel down hill and behind the firewall, isolating the gaseous gas with its heat= at the top of the line. =A0Turning the pumps on will pressurize the line t= o 55psi, returning most of the gaseous fuel back to a liquid state. =A0The = ECM is programmed for a longer clearing pulse on hot start.

The point of the bleed is to allow fuel to move back to the tank. =A0I = had the issue of a the pressurized lines being perfectly sealed. =A0The pre= ssurized fuel was finding the path of least resistance out, which just happ= ened to be out the injector and into the intake manifold where it sat as a = little puddle. =A0Heat soaking the lines would not push liquid fuel downhil= l and back behind the firewall. =A0It would push more fuel into the manifol= d. =A0A puddle of gas sitting in a composite manifold, just above a hot exh= aust stack is just bad mojo. =A0A poorly sealed regulator allows the pressu= re to bleed off in about 5 seconds (give or take), isolating the hot fuel in front of the firewall, and keeping the rest cool= and out of the intake manifold.

Got nuthin' to do with vapor lo= ck.

--
Homepage: =A0http://www.flyrotary.co= m/
Archive and UnSub: =A0 http://mail.lancairon= line.net:81/lists/flyrotary/List.html




--
= Homepage:=A0 http:/= /www.flyrotary.com/
Archive and UnSub:=A0 http://mail.= lancaironline.net:81/lists/flyrotary/List.html



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