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 5096477 for flyrotary@lancaironline.net; Thu, 18 Aug 2011 14:14:49 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.52; envelope-from=msteitle@gmail.com Received: by fxd18 with SMTP id 18so1436035fxd.25 for ; Thu, 18 Aug 2011 11:14:13 -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=o9vllA/8+r2ILBmQiiHZMb0pQyC9plMAky3O440M83c=; b=TVSEfxQlXa3RC0G37W/04kBDcQOxf0MOG2D7UQ2uDqqguSWXUjLKaUDHNl35XoJwXt FAtld8dVPI+iHUASkUJWXEkOKNrVgxn4b8pqYkW0Dn/Xx8dVYG+IV6PuPfIZtjj5ix1E HPJUmNAZhwsKRly6JHcoC9prMZxvrAX9afa14= MIME-Version: 1.0 Received: by 10.223.88.204 with SMTP id b12mr1471283fam.94.1313691253810; Thu, 18 Aug 2011 11:14:13 -0700 (PDT) Received: by 10.223.74.129 with HTTP; Thu, 18 Aug 2011 11:14:13 -0700 (PDT) In-Reply-To: References: Date: Thu, 18 Aug 2011 13:14:13 -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=000e0cd5301087262104aacb9493 --000e0cd5301087262104aacb9493 Content-Type: text/plain; charset=ISO-8859-1 Kelly, You can use a -16, but you'll still be limited by the inlet/outlet size of the Andair valve. I'm using -8 supply with a -6 return. These were upsized from original -6/-4 called for in the plans. Mark On Thu, Aug 18, 2011 at 12:37 PM, Kelly Troyer wrote: > Al, > Sounds like fuel line to the EFI pump (external pump) needs to be about > AN-8 or > even AN-10 instead of the typical AN-6 used by most............ > > Kelly Troyer > *"DYKE DELTA JD2" (Eventually)* > "13B ROTARY"_ Engine > "RWS"_RD1C/EC2/EM2 > "MISTRAL"_Backplate/Oil Manifold > "TURBONETICS"_TO4E50 Turbo > > *From:* Al Wick > > *To:* Rotary motors in aircraft > *Sent:* Thursday, August 18, 2011 12:15 PM > > *Subject:* [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, > for that matter. > > < Mark's problem can best be described as an "Air > > I'd describe it as not having "wet fuel inlet". When you turn that fuel > valve "on" the first time, if inlet gets wet, you've nailed an important > design characteristic. > You can simulate this with clear hose and water. Seal off one end of hose. > No air leaks allowed. Then pour water in other end. If water makes it to > closed end, you've got a good design. It's that simple. > You'll notice that small diam hose doesn't behave the same. What happens > when I add filter to the hose? What if I put a loop in the line? You are > asking the air at capped end to displace. The air has to be able to move > toward open end of tube. Play with it, pretty interesting. > > If your plumbing is already done, you can tape clear hose to plumbing and > do the test with water. > > All you are doing is converting theory to facts. Important concept. > > -al wick > > > ----- Original Message ----- > > *From:* Kelly Troyer > *To:* Rotary motors in aircraft > *Sent:* Wednesday, August 17, 2011 12:40 PM > *Subject:* [FlyRotary] Dennis Haverlah Fuel System...or any others, for > that matter. > > Al , Mark , Ernest and All, > > Perhaps a name change for the problem is in order.............Instead of > an > actual "Fuel Vapor Lock" Mark's problem can best be described as an "Air > Lock" in the pressure line (Or Air Entrapment Lock)..........Ernest's > problem > of injectors that leak down fuel (into the manifold or the engine with > potential > flooding or the fire hazard of dripping fuel in the cowl) has the same > solution > (bypass orifice) either external or internal to the regulator.......Both > problems > no matter what you call them can be cured with the same > solution............. > > Al as for the leaky injectors it would be great if these things did not > wear > over time but they do eventually become unable to hold pressure and will > exhibit leak-down at some rate........Unfortunately the Rotary engine is > much > more prone to flooding and hard starting if this fuel ends up in the Rotor > chamber..........If the primary injectors are left in their stock positions > and are > leaky this is a direct route to the Rotor............The secondary > injectors may > or may not be a problem depending position and/or manifold > design........... > > The bottom line is both potential problems can be averted with a > simple > bypass orifice.............As for an actual "Fuel Vapor Lock" as you say > this is > a different problem and can be addressed by careful attention to fuel pump > positioning (external or in-tank) ,supply tube (or hose) size, low > restriction > filters to pump inlet, heat shielding if appropriate, > etc................IMHO > > 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 1:46 PM > > *Subject:* [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, > for that matter. > > Al, > > You wrote,*"You also test it without the bleed line?"** * > > Yes, the test led to the search for a solution. You can see the "bypass > circuit" on Egg's fuel system schematic at > http://www.eggenfellneraircraft.com/Manual-Updates/EarlyManualFuel.html. > This is what I incorporated into my fuel system, and it solved the problem. > Its been quite a few years now, but I may still have some of the posts on > the Eggenfellner list that occurred in search for this as the final > solution. > > You wrote,*"FWIW, everything you describe is not vapor lock, has nothing > to do with vapor lock." * > > As I said, I'm not sure if my condition fits the definition of "vapor > lock", but that's what someone labeled it, and it stuck. The problem is > that EFI pumps don't draw or push air very well. So, if the flowing fuel > is replaced by air due to an empty tank, the pump keeps running, but > essentially stops pumping fuel. With a 40# spring in the downstream > circuit, it is virtually impossible for the pump to pass the air even > though the selector valve has been swiched to the full tank. I would > agree that the fuel injectors should be able to pass the air, provided the > prop is still turning. (This was not the case with my ground test.) The > bypass circuit ensures that flow will be restored as soon as the > bubble passes through the pump and the fuel pump regains its prime. > > Mark S. > > On Wed, Aug 17, 2011 at 12:06 PM, Al Wick wrote: > > ** > low as possible > > Instead of speculations, you can actually measure how good it is. A pump, > clear fuel lines, and water instead of fuel. Pinch fuel line with pliers to > increase pressure drop. Watch bubbles come out of solution. Hear the rattle > from pump due to it's inability to flow air. > If you also put a pressure gage on pump inlet, you can see how fine fuel > filter increases risk. You can see how small diameter tubing increases risk, > heat, head pressure, etc etc. > > Egg had one forced landing. It was caused by vapor lock. Absolutely NOTHING > to do with the lack of bleed line. A day later, Jan made it to the crash > site. Pump would not flow fuel until he cracked the line loose. This is > simply because the inlet to pumps was not wet. He did not understand this. > He just reacted to symptoms. Nothing to do with vapor lock. Remember, this > was crash site. Who knows what attitude plane was at. As I described, if you > screwed up your plumbing from tank to pump, then pump is not self priming. > > You also test it without the bleed line? > > FWIW, everything you describe is not vapor lock, has nothing to do with > vapor lock. > > -al wick > > > ----- Original Message ----- > *From:* Mark Steitle > *To:* Rotary motors in aircraft > *Sent:* Wednesday, August 17, 2011 9:19 AM > *Subject:* [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, > for that matter. > > 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 > > > > > --000e0cd5301087262104aacb9493 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Kelly,=A0

You can use a -16, but you'll still be lim= ited by the inlet/outlet size of the Andair valve. =A0I'm using -8 supp= ly with a -6 return. =A0These were upsized from original -6/-4 called for i= n the plans. =A0

Mark

On Thu, Aug 18, = 2011 at 12:37 PM, Kelly Troyer <keltro@att.net> wrote:
Al,
=A0 Sounds like fuel line to the EFI pump (external pump) needs = to be about AN-8 or
even AN-10 instead of the typical AN-6 used by most............<= var>
=A0
Kelly Troyer
"DYKE DELTA JD2" = (Eventually)
"13B ROTARY"_ Engine
"RWS"_RD1C/EC2/EM2
&quo= t;MISTRAL"_Backplate/Oil Manifold
"TURBONETICS"_TO4E50 Turbo

From: Al Wick <alwick@juno.com>
To: Rotar= y motors in aircraft <flyrotary@lancaironline.net>
Sent: Thursday, August= 18, 2011 12:15 PM

Subject: [FlyRotary] Re: Dennis Haverlah Fuel System...or any o= thers, for that matter.

<=A0Mark's problem can best be = described as an "Air=20
<Lock" in the pressure line
=A0
I'd describe it as not having "wet fuel inlet". Wh= en you turn that fuel valve=A0"on" the first time, if inlet gets = wet, you've nailed an important design characteristic.
You can simulate this with clear hose and water. Seal off one en= d of hose. No air leaks allowed. Then pour water in other end. If water mak= es it to closed end, you've got a good design. It's that simple.
You'll notice that small diam hose doesn't behave the sa= me. What happens when I add filter to the hose? What if I put a loop in the= line? You are asking the air at capped end to displace. The air has to be = able to move toward open end of tube. Play with it, pretty interesting.
=A0
If your plumbing is already done, you can tape clear hose to plu= mbing and do the test with water.
=A0
All you are doing is converting theory to facts. Important conce= pt.
=A0
-al wick
=A0
=A0
----- Original Message -----
Sent: Wednesday, August 17, 201= 1 12:40 PM
Subject: [FlyRotary] Dennis Haverlah = Fuel System...or any others, for that matter.

Al , Mark , Ernest=A0and All,
=A0
=A0 Perhaps a=A0name change for the problem is in order.........= ....Instead of an
actual "Fuel Vapor Lock" Mark's problem can best b= e described as an "Air
Lock" in the pressure line=A0(Or Air Entrapment Lock)......= ....Ernest's problem
of injectors that leak down fuel (into the manifold or the engin= e with potential
flooding or the fire hazard of dripping fuel in the cowl) has th= e same solution
(bypass orifice) either e= xternal or internal to the regulator.......Both problems
no matter what you call them can be cured with the same solution= .............
=A0
=A0=A0 =A0Al as for the leaky injectors it would be great if the= se things did not wear
over time but they do eventually become unable to hold pressure = and will
exhibit leak-down at some= rate........Unfortunately the Rotar= y engine is much
more prone to flooding and hard starting if this fuel ends up in= the Rotor
chamber..........If the primary injectors=A0are left in their st= ock positions and are
leaky this is a direct route to the Rotor............The seconda= ry injectors may
or may not be a problem depending position and/or manifold desig= n...........
=A0=A0
=A0=A0=A0=A0The bottom line is both potential<= /span> problems can be averted with a simple
bypass orifice...........= ..As for an actual "Fuel Vapor Lock" as you say this is
a different problem and can be addressed by careful attention to= fuel pump
positioning (external or in-tank= ) ,supply tube (or hose) size, low restriction
filters to pump inlet, heat shielding if appropriate, etc....= ............IMHO=A0
=A0
Kelly Troyer
"DYKE DELTA JD2" (Eventually)
"13B ROTARY"_ Engine
"RWS&= quot;_RD1C/EC2/EM2
"MISTRAL"_Backplate/Oil Manifold
"TURBONETICS"_TO4E50 Turbo

From: Mark Steitle <msteitle@gmail.com>
T= o: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wednesday, Augus= t 17, 2011 1:46 PM

Subject: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, for that matter.

Al,
=A0
You wrote,"You also test it without the bleed line?"=A0
=A0
Yes, the test led to the search for a solution.=A0 You can see the &qu= ot;bypass circuit" on Egg's fuel system schematic at http://www.eggenfellneraircraft.com/Manual-= Updates/EarlyManualFuel.html.=A0 This is=A0what I=A0incorporated into m= y=A0fuel system, and it solved the problem.=A0 Its been quite a few years n= ow, but I=A0may still have=A0some of the posts on the Eggenfell= ner=A0list=A0that occurred in search for this as the final so= lution.
=A0
You wrote,"FWIW, everything you= describe is not vapor lock, has nothing to do with vapor lock."=A0
=A0
As I said, I'm not sure if my condition fits the definition of &qu= ot;vapor lock", but that's what someone labeled it, and it stuck.= =A0 The problem is that EFI pumps don't=A0dra= w or push air very well.=A0 So, if the flowing fuel is replaced by air due = to an empty tank, the pump keeps running, but essentially=A0stops pumping f= uel.=A0 With a 40# spring in the downstream circuit, it is virtually imposs= ible for the pump to pass the air=A0even though=A0the selector valve has be= en swiched to the full tank.=A0 I would agree tha= t the fuel injectors should be able to pass the air, provided the prop is s= till turning.=A0 (This was not the case with my ground test.) The bypass ci= rcuit ensures that flow will=A0be restored as soon as the bubble=A0passes t= hrough the pump and=A0the fuel pump regains its prime.=A0
=A0
Mark S.

On Wed, Aug 17, 2011 at 12:06 PM, Al Wick <alwick@juno.com> wrote:
<I would think that a well-designed fuel system with the pumps loca= ted as low as possible
=A0
Instead of speculations, you can= actually measure how good it is. A pump, clear fuel lines, and water inste= ad of fuel. Pinch fuel line with pliers to increase pressure drop.=A0 Watch= bubbles come out of solution. Hear the rattle from pump due to it's in= ability to flow air.
If you also put a pressure gage on pum= p inlet, you can see how fine fuel filter increases risk. You can see how s= mall diameter tubing increases risk, heat, head pressure, etc etc. <= /div>
=A0
<the result of a forced landing
Egg had one forced landing. It was caused by vapor lock. Absolut= ely NOTHING to do with the lack of bleed line. A day later, Jan made it to = the crash site. Pump would not flow fuel until he cracked the line loose. T= his is simply because the inlet to pumps was not wet. He did not understand= this. He just reacted to symptoms. Nothing to do with vapor lock. Remember= , this was crash site. Who knows what attitude plane was at. As I described= , if you screwed up your plumbing from tank to pump, then pump is not self = priming.
=A0
<tested this system on the ground and it works as adver= tized
You also test it without the bleed line?
=A0
FWIW, everyt= hing you describe is not vapor lock, has nothing to do with vapor lock.
=A0
-al wick
=A0
----- Original Message -----
Sent: Wednesday, August 17, 2011 9:19= AM
Subject: [FlyRotary] Re: Dennis Haverlah Fuel System...or any others, for that matter.=

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-gallon can, I found that the efi= fuel pumps could not restore pressure once the tank had been allowe= d to run dry.=A0=A0When this occurred, the EFI pu= mp=A0would suck a big slug of air into the inlet side of the pump, loose pr= essure,=A0and being unable to build psi equal to the pressure regulator set= ting, it would stop pumping fuel (vapor lock).=A0 The only way to restore o= peration was to crack open the system downstream of the pump until the slug= of air could be passed on through the fuel pump.=A0=A0Not sure this meets your definiton= of "vapor lock", but I think it does, but for a di= fferent reason than fuel vapor pressure.
=A0
I have tested this system on the ground and it works as ad= vertized.=A0 If the tank runs dry, switched to a full tank, t= he efi pump will restore pressure to the system w= ithin a few seconds.=A0 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.=A0 Or, just don't ever run a tank dry.
=A0
Mark S.


=A0
On Wed, Aug 17, 2011 at 10:22 AM, Ernest Christley<= /span> <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 t= he top of the line. =A0Turning the pumps on will pressurize the line to 55p= si, returning most of the gaseous fuel back to a liquid state. =A0The ECM is programmed for a longer clearing pulse on hot s= tart.

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 r= egulator 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 coo= l and out of the intake manifold.

Got nuthin' to do with vapor lock.

--
Homepage: =A0http://www.flyrotary.com/
= Archive and UnSub: =A0 http://mail.lancaironline.net:81/lists/flyrotary/List.html

<= /div>

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

<= br>



--000e0cd5301087262104aacb9493--