X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.121] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTP id 5111212 for flyrotary@lancaironline.net; Thu, 01 Sep 2011 22:51:42 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.121; envelope-from=eanderson@carolina.rr.com Return-Path: X-Authority-Analysis: v=1.1 cv=4MSDN839FDsgJpwQlr+eLEnlTy8eaQTddc4+Fk+GTfI= c=1 sm=0 a=7Qa_3ZkZZvgA:10 a=SC71y0a/4S6V9vjVxUojGA==:17 a=vggBfdFIAAAA:8 a=3oc9M9_CAAAA:8 a=V0sYiUSkAAAA:8 a=ayC55rCoAAAA:8 a=Ia-xEzejAAAA:8 a=arxwEM4EAAAA:8 a=r1ClD_H3AAAA:8 a=o9KuFcxMAAAA:8 a=4WcNE56ytDaxU9muEPwA:9 a=OJvod185kEffVuhyQD0A:7 a=wPNLvfGTeEIA:10 a=XptUGg1y60QA:10 a=U8Ie8EnqySEA:10 a=EzXvWhQp4_cA:10 a=GhIjh3UBWcwA:10 a=TYVMWhhuW_uHyKqr:21 a=_cg0qNY75OsCInas:21 a=pedpZTtsAAAA:8 a=4PR2P7QzAAAA:8 a=L4wwTDsDnzpjTsC0-OUA:9 a=Jk2PjDbm0SOxybThOmsA:7 a=tXsnliwV7b4A:10 a=eJojReuL3h0A:10 a=djSSOgbfo6cA:10 a=SC71y0a/4S6V9vjVxUojGA==:117 X-Cloudmark-Score: 0 X-Originating-IP: 174.110.175.135 Received: from [174.110.175.135] ([174.110.175.135:61771] helo=EdPC) by cdptpa-oedge03.mail.rr.com (envelope-from ) (ecelerity 2.2.3.46 r()) with ESMTP id A2/F5-28959-994406E4; Fri, 02 Sep 2011 02:51:05 +0000 Message-ID: <7AAE9600EF7445948699F90D38B806F0@EdPC> From: "Ed Anderson" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Pump Suck Lock? Date: Thu, 1 Sep 2011 22:51:01 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0045_01CC68F9.9F57AB50" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8117.416 X-MIMEOLE: Produced By Microsoft MimeOLE V14.0.8117.416 This is a multi-part message in MIME format. ------=_NextPart_000_0045_01CC68F9.9F57AB50 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable For what is worth, Charlie My "sump" is a small header tank (approx 3/4 pint) on the front of my = firewall as low down as I could get it. I return fuel from my pressure = regulator to his small header tank and have two fittings on the bottom - = one for each EFI tank to "suck" through. So in effect each pump is = pulling from the header tank. There is also a vapor space volume at = the top of this small tank - which the fuel is returned to from the = pressure regulator. So this design tries to provide a space for any = vapor (top of tank) separate from where the liquid fuel is (bottom of = tank). This avoided any returns back to the main tanks - worked for me. Ed From: Charlie England=20 Sent: Thursday, September 01, 2011 9:14 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Pump Suck Lock? Here are a few examples of typical in-tank pumps: http://www.amazon.com/s/ref=3Dnb_sb_noss?url=3Dsearch-alias%3Daps&field-k= eywords=3Dford+fuel+pump+assembly&x=3D0&y=3D0 There's typically a 'sock' type strainer on the inlet, and a mechanical = bypass type pressure regulator on the pump's output, buried in that mass = you see in the pics. I suspect that it is needed as a 'fuse' to prevent = blowing something out if a line gets blocked somewhere downstream. A = float type level sender is usually in there, too. The sump idea is unattractive to me for my my application (low wing = plane) because I worry about it air-locking, unless I provide a vent = back to the main tank, which is even more complicated. (I've owned a = high wing homebuilt that used sumps, but they were vented back into the = wing tanks.) Charlie On 09/01/2011 04:51 PM, CozyGirrrl@aol.com wrote:=20 1. So there's no issues with hot soaked restarts of an EFI engine? 2. We have a pair of Walbro GSL393 EFI pumps, suitable for in or out = of tank mounting though I am curious how they were tank mounted. 3. Check valves. I thought that these pumps would not free flow either = direction if shut off thereby not needing check valves? 4. If an EFI pump were mounted in a sump of approximately 1.5 qt = capacity, this fed by a low volume/low pressure Facet pump from the main = tank, between the heat generated by the pump itself and picked up in the = circuit, would the flow of the facet pump replenishing used fuel with = the excess returning to the main tank keep the pump, sump and circuit = fuel at a reasonable temp? What would the minimum volume be? Keep in mind that the circuit fuel is mixing with the replenished fuel = so some heat is going as overflow back to the main tanks. Chrissi & Randi www.CozyGirrrl.com CG Products, Custom Aircraft Hardware Chairwomen, Sun-N-Fun Engine Workshop In a message dated 9/1/2011 2:39:12 P.M. Central Daylight Time, = shipchief@aol.com writes: I'm running two of Tracy's original fuel pump offerings, in parallel = in my RV-8. I have finger strainers in the tanks, then thru Van's fuel = selector valve, forward to the pumps. The pumps are mounted to the floor = next to the left rudder pedal. Each pump discharges thru a vertical = mounted check valve on the back of the firewall, then joins to the = bulkhead fitting and on to a High pressure filter and on to the fuel = injectors, in series. The stock Mazda pressure regulator is the last = point, then to the fuel return selector valve and to the tank. All -6 = tube and hose. I didn't like the original Van's fuel tank pick ups, so I used John = Ammter's design, which is a finger strainer in a doubler plate at the = aft lower corner of the inboard fuel tank rib. I don't think I can get much better, unless I put a hatch in the top = of the tank and use an 'In Tank' fuel pump. Then I'll lose some = redundancy and need to change the operating proceedure...I'll have to = think about that one.... My secondary injectors are mounted somewhat like the Cozygrrls' = lower manifold, but outboard instead of inboard of the tubes. This is = above the exhaust manifold, so I have cooling air directed in from the = left cowl inlet. It feels pretty warm in there after a test run. -----Original Message----- From: Ed Anderson To: Rotary motors in aircraft Sent: Thu, Sep 1, 2011 5:34 am Subject: [FlyRotary] Pump Suck Lock?: [FlyRotary] Re: CG Products = Intake Manifold I don't see any problem with the term "vapor lock" itself - because = when the pressure on the pump inlet gets low enough, that is exactly = what happens - sufficient fuel enters a gaseous state to interfere with = the pumping of liquid fuel to the high pressure side. So the term is = not that bad a description so long as we all realize it happens on the = Low pressure (inlet) side of the pump and NOT the high pressure side. =20 My experience with "vapor lock" showed that by turning my boost pump = on (adding pressure to the "suction " side of the EFI high pressure = pump) eliminated the condition - which again indicates the problem is = low pressure on the inlet side of the EFI pump. If there were liquid = there, it would be pumped, so must be vapor - so the pump is "vapor = locked" but, - not on the high pressure side. =20 Perhaps we should refer to a more technical accurate descriptive = name , how about "Pump Suck Lock" {:>) - just kidding. Ed=20 Edward L. Anderson Anderson Electronic Enterprises LLC 305 Reefton Road Weddington, NC 28104 http://www.andersonee.com http://www.eicommander.com =20 From: Charlie England=20 Sent: Wednesday, August 31, 2011 3:07 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: CG Products Intake Manifold Data point: One of the big aviation engine/fuel injection suppliers = installs -4 lines everywhere in front of the firewall up to the = 'spider', on all 4 cyl Lycs (up to 200+ hp) and if memory serves, even = on the 6cyl engines (230+ hp). The individual lines from the 'spider' to = the cylinders are so small you'd be hard pressed to get safety wire = through them. This is on a Bendix style injection system using a = diaphragm type fuel pump and no return line after the pump. These = systems run at between 15 & 30 psi. Logic is that minimum diameter line = minimizes quantity of fuel that can boil on the engine side of the = firewall.=20 With minimum diameter lines, as long as the pump can provide = pressure it won't take long to clear any vapor as soon as cranking = begins, or you hit Tracy's 'cold start' button a couple of times. (Vapor = in the combustion chamber is a good thing anyway, right?) :-) As Al Wick pointed out, the only place vapor should be a problem is = at the inlet to the pump itself. Charlie On 08/31/2011 07:35 AM, CozyGirrrl@aol.com wrote:=20 Interesting Chad. The people flying Subes and using autogas were also guessing that = altitude was a factor in vaporlock. We won't be using autogas due to = variable formulation eating up epoxy tanks. We were thinking that if the regulator was the last item in the = chain and that the rails were hooked up serially that it would minimize = vaporlock and also a few seconds of the pump running before a hot = restart would cool and clear the rail. Chrissi & Randi www.CozyGirrrl.com CG Products, Custom Aircraft Hardware Chairwomen, Sun-N-Fun Engine Workshop In a message dated 8/30/2011 11:36:05 P.M. Central Daylight Time, = crobinson@medialantern.com writes: I recently researched EFI regulation a bit and found something = interesting. Many modern (post-1995) vehicles have "returnless" EDI = systems where the regulator is in or near the tank, not the engine = compartment. It turns out this isn't for complexity reasons, though it does = save a bit. It's for emissions. The heating of the fuel in the engine = compartment transfers heat back to the tank. The tank's emissions do = count even though they're not huge. It's also one less part, hose, and = set of fittings to fail- and get warranty calls on. To deal with vapor lock they just crank up the pressure to 65 or = more psi. Very effective. Not at all saying we should do the same, but the purpose is = interesting, no? As well as the vapor lock" solution"... Regards, Chad ------=_NextPart_000_0045_01CC68F9.9F57AB50 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
For what is worth, Charlie
 
My "sump" is a small header tank = (approx 3/4=20  pint) on the front of my firewall as low down as I could get = it.  I=20 return fuel from my pressure regulator to his small header tank and have = two=20 fittings on the bottom - one for each EFI tank to "suck" = through. So in=20 effect each pump is pulling from the header tank.   There is = also a=20 vapor space volume at the top of this small tank - which the fuel is = returned to=20 from the pressure regulator.  So this design tries to provide a = space for=20 any vapor (top of tank) separate from where the liquid fuel is (bottom = of=20 tank).  This avoided any returns back to the main tanks - worked = for=20 me.
 
Ed

Sent: Thursday, September 01, 2011 9:14 PM
Subject: [FlyRotary] Re: Pump Suck Lock?

Here are a few examples of typical in-tank pumps:
http:/= /www.amazon.com/s/ref=3Dnb_sb_noss?url=3Dsearch-alias%3Daps&field-key= words=3Dford+fuel+pump+assembly&x=3D0&y=3D0

There's=20 typically a 'sock' type strainer on the inlet, and a mechanical bypass = type=20 pressure regulator on the pump's output, buried in that mass you see in = the=20 pics. I suspect that it is needed as a 'fuse' to prevent blowing = something out=20 if a line gets blocked somewhere downstream. A float type level sender = is=20 usually in there, too.

The sump idea is unattractive to me for my = my=20 application (low wing plane) because I worry about it air-locking, = unless I=20 provide a vent back to the main tank, which is even more complicated. = (I've=20 owned a high wing homebuilt that used sumps, but they were vented back = into the=20 wing tanks.)

Charlie

On 09/01/2011 04:51 PM, CozyGirrrl@aol.com wrote:=20
1. So there's no issues with hot soaked restarts of an EFI = engine?
 
2. We have a pair of Walbro GSL393 EFI pumps, suitable = for in or out=20 of tank mounting though I am curious how they were tank mounted.
 
3. Check valves. I thought that these pumps would not free flow = either=20 direction if shut off thereby not needing check valves?
 
4. If an EFI pump were mounted in a sump of approximately 1.5 qt=20 capacity, this fed by a low volume/low pressure Facet pump from the = main tank,=20 between the heat generated by the pump itself and picked up in the = circuit,=20 would the flow of the facet pump replenishing used fuel with the = excess=20 returning to the main tank keep the pump, sump and circuit fuel at a=20 reasonable temp? What would the minimum volume be?
Keep in mind that the circuit fuel is mixing with the replenished = fuel so=20 some heat is going as overflow back to the main tanks.
 
Chrissi=20 & Randi
www.CozyGirrrl.com
CG Products, Custom = Aircraft=20 Hardware
Chairwomen, Sun-N-Fun Engine Workshop
 
In a message dated 9/1/2011 2:39:12 P.M. Central Daylight Time, = shipchief@aol.com writes:
I'm running two of Tracy's original fuel pump offerings, in = parallel in=20 my RV-8. I have finger strainers in the tanks, then thru Van's fuel = selector=20 valve, forward to the pumps. The pumps are mounted to the floor next = to the=20 left rudder pedal. Each pump discharges thru a vertical mounted = check valve=20 on the back of the firewall, then joins to the bulkhead fitting and=20 on to a High pressure filter and on to the fuel injectors, in = series.=20 The stock Mazda pressure regulator is the last point, then to the = fuel=20 return selector valve and to the tank. All -6 tube and hose.
I didn't like the original Van's fuel tank pick ups, so I used = John=20 Ammter's design, which is a finger strainer in a doubler plate at = the aft=20 lower corner of the inboard fuel tank rib.
I don't think I can get much better, unless I put a hatch in = the top of=20 the tank and use an 'In Tank' fuel pump. Then I'll lose some = redundancy and=20 need to change the operating proceedure...I'll have to think about = that=20 one....
My secondary injectors are mounted somewhat like the Cozygrrls' = lower=20 manifold, but outboard instead of inboard of the tubes. This is = above the=20 exhaust manifold, so I have cooling air directed in from the = left cowl=20 inlet. It feels pretty warm in there after a test = run.



-----Original=20 Message-----
From: Ed Anderson <eanderson@carolina.rr.com&g= t;
To:=20 Rotary motors in aircraft <flyrotary@lancaironline.n= et>
Sent:=20 Thu, Sep 1, 2011 5:34 am
Subject: [FlyRotary] Pump Suck Lock?:=20 [FlyRotary] Re: CG Products Intake Manifold

I don't see any problem with the term "vapor = lock"=20 itself - because when the pressure on the pump inlet gets low = enough, that=20 is exactly what happens - sufficient fuel enters a gaseous = state=20 to interfere with the pumping of liquid fuel to the high pressure=20 side.  So the term is not that bad a description so long as we = all=20 realize it happens on the Low pressure (inlet)  side of the = pump and=20 NOT the high pressure side. 
 
My experience with "vapor lock" showed that = by turning=20 my boost pump on (adding pressure to the "suction " side of the EFI = high=20 pressure pump) eliminated the condition - which again indicates the = problem=20 is low pressure on the inlet side of the EFI pump.  If = there were=20 liquid there, it would be pumped, so must be vapor - so the pump is = "vapor=20 locked" but, - not on the high pressure side.   =
 
Perhaps we should refer to a more technical = accurate=20 descriptive name , how about  "Pump = Suck Lock"=20 {:>) - just kidding.
 
 
Ed 
 
 Edward L. Anderson
Anderson = Electronic=20 Enterprises LLC
305 Reefton Road
Weddington, NC 28104
http://www.andersonee.com
http://www.eicommander.com
 
 
 
 

 
Sent: Wednesday, August 31, 2011 3:07 PM
Subject: [FlyRotary] Re: CG Products Intake=20 Manifold

Data point: One of the big aviation engine/fuel = injection=20 suppliers installs -4 lines everywhere in front of the firewall up = to the=20 'spider', on all 4 cyl Lycs (up to 200+ hp) and if memory serves, = even on=20 the 6cyl engines (230+ hp). The individual lines from the 'spider' = to the=20 cylinders are so small you'd be hard pressed to get safety wire = through=20 them. This is on a Bendix style injection system using a diaphragm = type fuel=20 pump and no return line after the pump. These systems run at between = 15=20 & 30 psi. Logic is that minimum diameter line minimizes quantity = of fuel=20 that can boil on the engine side of the firewall.

With = minimum=20 diameter lines, as long as the pump can provide pressure it won't = take long=20 to clear any vapor as soon as cranking begins, or you hit Tracy's = 'cold=20 start' button a couple of times. (Vapor in the combustion chamber is = a good=20 thing anyway, right?) :-)

As Al Wick pointed out, the only = place=20 vapor should be a problem is at the inlet to the pump=20 itself.

Charlie

On 08/31/2011 07:35 AM, CozyGirrrl@aol.com wrote:=20
Interesting Chad.
The people flying Subes and using autogas were also guessing = that=20 altitude was a factor in vaporlock. We won't be using autogas due = to=20 variable formulation eating up epoxy tanks.
We were thinking that if the regulator was the last item in = the chain=20 and that the rails were hooked up serially that it would minimize=20 vaporlock and also a few seconds of the pump running before a hot = restart=20 would cool and clear the rail.
 
Chrissi & = Randi
www.CozyGirrrl.com
CG=20 Products, Custom Aircraft Hardware
Chairwomen, Sun-N-Fun Engine = Workshop
 
In a message dated 8/30/2011 11:36:05 P.M. Central Daylight = Time, crobinson@medialantern.com = writes:
I recently researched EFI regulation a bit and found = something=20 interesting. Many modern (post-1995) vehicles have "returnless" = EDI=20 systems where the regulator is in or near the tank, not the = engine=20 compartment.
It turns out this isn't for complexity reasons, though it = does save=20 a bit. It's for emissions. The heating of the fuel in the engine = compartment transfers heat back to the tank. The tank's = emissions do=20 count even though they're not huge. It's also one less part, = hose, and=20 set of fittings to fail-  and get warranty calls on.
To deal with vapor lock they just crank up the pressure to = 65 or=20 more psi. Very effective.
Not at all saying we should do the same, but the purpose is = interesting, no? As well as the vapor lock" solution"...
=
Regards,
Chad
=


------=_NextPart_000_0045_01CC68F9.9F57AB50--