X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from qmta10.emeryville.ca.mail.comcast.net ([76.96.30.17] verified) by logan.com (CommuniGate Pro SMTP 5.4c2o) with ESMTP id 4882241 for flyrotary@lancaironline.net; Fri, 25 Feb 2011 06:41:44 -0500 Received-SPF: pass receiver=logan.com; client-ip=76.96.30.17; envelope-from=wschertz@comcast.net Received: from omta12.emeryville.ca.mail.comcast.net ([76.96.30.44]) by qmta10.emeryville.ca.mail.comcast.net with comcast id CBfk1g0010x6nqcAABh7ab; Fri, 25 Feb 2011 11:41:07 +0000 Received: from WschertzPC ([75.224.91.26]) by omta12.emeryville.ca.mail.comcast.net with comcast id CBgq1g00D0a7MLB8YBguHg; Fri, 25 Feb 2011 11:41:05 +0000 Message-ID: From: "Bill Schertz" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Fwd: Fuel injector pump cooling?? Date: Fri, 25 Feb 2011 05:40:46 -0600 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0058_01CBD4AE.8D159130" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 15.4.3502.922 X-MimeOLE: Produced By Microsoft MimeOLE V15.4.3502.922 This is a multi-part message in MIME format. ------=_NextPart_000_0058_01CBD4AE.8D159130 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Charlie, I would caution about your using a selector =E2=80=98normally=E2=80=99 = and returning to only one tank. I believe that it puts too much workload = on the pilot, especially when you don=E2=80=99t have max fuel. I = don=E2=80=99t know about RV=E2=80=99s, but my experimental (KIS) shows = a definite development of the tendency to turn towards the heavy tank = when they get very far out of balance due to uneven fuel content. At = about 5 gallons difference in the tanks, I start to have to apply steady = pressure to the ailerons to correct it. So, if you are getting low down = to half tanks, and start drawing from the non-return tank, it might not = take very long to deplete that tank with the excess fuel being dumped = into the return tank. Our pumps move the fuel rather fast, faster (I = believe) than the certified planes that use that system. A prototype = Pulsar with the system as you described had this problem during an early = test flight when he started with ~10 gallons in each tank, switched to = the non-return tank, and ran out of gas much faster than expected, = couldn=E2=80=99t get the pump to prime in time from the other tank, and = had an off field landing. Andair makes a nice duplex valve that returns the fuel to the tank it = came from. Costs a lot less than an off field landing. FWIW =20 Bill Schertz KIS Cruiser #4045 N343BS Phase one testing Completed From: Charlie England=20 Sent: Thursday, February 24, 2011 5:18 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Fwd: Fuel injector pump cooling?? Ouch; I hadn't thought about that. But I suspect that even a low = pressure pump would damage the tank if the vent is blocked. Thanks for = the data point on the fact that a high pressure pump can be used = effectively as a transfer pump. Were you using a separate port on the main tank for your transfer point? = My tentative plan is to T into either the regulator return, or (assuming = an effective back/anti-siphon setup), into the main supply between tank = & engine pump. Obviously, the anti-siphon feature would need to be = bullet proof to tap the supply line. One option I've considered is to use the fuel selector 'normally', but = have all regulator bypass return to a single 'main' tank. This = arrangement is actually used in some certified planes with injected = Continentals, but I'm leery of having my primary engine pump run dry for = even a very short interval as I empty an aux tank. I suppose that with = that arrangement, it would only run dry for a couple of seconds ( :-> ), = so maybe it would work out fine. Any thoughts? Charlie On 2/24/2011 2:36 PM, Steven W. Boese wrote:=20 Charlie, =20 I initially had my RV set up with a Facet transfer pump with an = external check valve. The check valve spring was replaced with a = slightly stronger one so that it served both the anti back flow and anti = siphon functions. The high percentage of the time that the Facet = transfer pump was operating convinced me to change to the type (not the = exact part) of pump you are considering. The pump seemed reliable but = after a couple of instances of transferring fuel out the receiving = tank=E2=80=99s vent in spite of a timer on the transfer pump, I = eliminated the transfer function altogether. The possibility of = applying up to 90 psi to the receiving tank if its vent malfunctioned = did not suit me. It would not take anywhere near this pressure to fail = the tank. The procedure for leak testing the fuel tanks cautions not to = apply even a couple of psi to them. The limitation here really was me, = though, not the equipment. =20 Steve Boese RV6A 1986 13B NA RD1A EC2 =20 =20 =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Charlie England Sent: Thursday, February 24, 2011 12:23 PM To: Rotary motors in aircraft Subject: [FlyRotary] Fwd: Fuel injector pump cooling?? =20 Anyone see any issues with one of the automotive in-tank pumps being = used outside the tank? Looking at the overall = pump/pickup/regulator/level sensor/etc assemblies in most auto fuel = tanks, it would appear that the pump itself would be above the level of = the fuel anyway if the tank is less than 1/4 full. I've been looking for a Facet transfer pump that has both a backflow = valve & an anti-siphon valve (40257 is one) but they are very hard to = find & expensive when you find them. During my search, I ran across = this: = http://www.amazon.com/gp/product/B000BMBSS0/ref=3Dpd_lpo_k2_dp_sr_3?pf_rd= _p=3D486539851&pf_rd_s=3Dlpo-top-stripe-1&pf_rd_t=3D201&pf_rd_i=3DB002YP4= Q3Q&pf_rd_m=3DATVPDKIKX0DER&pf_rd_r=3D1JFK34G48EBF5R93EB2Y The application appears to be 87-98 GM products. It appears to be very similar to the 'standard' in-line pump that = Tracy supplies, with the exception of plastic components in the output = end. Assuming that it's a positive displacement gear pump, it should = supply both the backflow & anti-siphon features I desire & at roughly = $30 shipped, it's cheaper than even the cheapest Facet 'solid state' = transfer pumps. I'm hoping that cooling/lube won't be an issue as long = as it isn't run 'dry' for more than a few seconds at the end of a = transfer cycle. Charlie ------=_NextPart_000_0058_01CBD4AE.8D159130 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
Charlie,
I would caution about your using a selector = =E2=80=98normally=E2=80=99 and returning to=20 only one tank. I believe that it puts too much workload on the pilot, = especially=20 when you don=E2=80=99t have max fuel. I don=E2=80=99t know about = RV=E2=80=99s, but  my experimental=20 (KIS) shows a definite development of the tendency to turn towards the = heavy=20 tank when they get very far out of balance due to uneven fuel content. = At about=20 5 gallons difference in the tanks, I start to have to apply steady = pressure to=20 the ailerons to correct it. So, if you are getting low down to half = tanks, and=20 start drawing from the non-return tank, it might not take very long to = deplete=20 that tank with the excess fuel being dumped into the return tank. Our = pumps move=20 the fuel rather fast, faster (I believe) than the certified planes that = use that=20 system.  A prototype Pulsar with the system as you described had = this=20 problem during an early test flight when he started with ~10 gallons in = each=20 tank, switched to the non-return tank, and ran out of gas much faster = than=20 expected, couldn=E2=80=99t get the pump to prime in time from the other = tank, and had an=20 off field landing.
 
Andair makes a nice duplex valve that returns the fuel to the tank = it came=20 from. Costs a lot less than an off field landing.
 
FWIW 
 
Bill=20 Schertz
KIS Cruiser #4045
N343BS
Phase one testing = Completed
 
Sent: Thursday, February 24, 2011 5:18 PM
Subject: [FlyRotary] Re: Fwd: Fuel injector pump=20 cooling??
 
Ouch;=20 I hadn't thought about that. But I suspect that even a low pressure pump = would=20 damage the tank if the vent is blocked. Thanks for the data point on the = fact=20 that a high pressure pump can be used effectively as a transfer=20 pump.

Were you using a separate port on the main tank for your = transfer=20 point? My tentative plan is to T into either the regulator return, or = (assuming=20 an effective back/anti-siphon setup), into the main supply between tank = &=20 engine pump. Obviously, the anti-siphon feature would need to be bullet = proof to=20 tap the supply line.

One option I've considered is to use the = fuel=20 selector 'normally', but have all regulator bypass return to a single = 'main'=20 tank. This arrangement is actually used in some certified planes with = injected=20 Continentals, but I'm leery of having my primary engine pump run dry for = even a=20 very short interval as I empty an aux tank. I suppose that with that=20 arrangement, it would only run dry for a couple of seconds ( :-> ), = so maybe=20 it would work out fine. Any = thoughts?



Charlie


On=20 2/24/2011 2:36 PM, Steven W. Boese wrote:=20

Charlie,

 

I initially = had my RV=20 set up with a Facet transfer pump with an external check valve.  = The=20 check valve spring was replaced with a slightly stronger one so that = it served=20 both the anti back flow and anti siphon functions.  The high = percentage=20 of the time that the Facet transfer pump was operating convinced me to = change=20 to the type (not the exact part) of pump you are  = considering.  The=20 pump seemed reliable but after a couple of instances of transferring = fuel out=20 the receiving tank=E2=80=99s vent in spite of a timer on the transfer = pump, I=20 eliminated the transfer function altogether.  The possibility of = applying=20 up to 90 psi to the receiving tank if its vent malfunctioned did not = suit=20 me.  It would not take anywhere near this pressure to fail the=20 tank.  The procedure for leak testing the fuel tanks cautions not = to=20 apply even a couple of psi to them.  The limitation here really = was me,=20 though, not the equipment.

 

Steve=20 Boese

RV6A 1986 = 13B NA RD1A=20 EC2

 

 

 

 

From:=20 Rotary motors in aircraft [mailto:flyrotary@lancaironlin= e.net]=20 On Behalf Of Charlie England
Sent: Thursday, February = 24,=20 2011 12:23 PM
To: Rotary motors in = aircraft
Subject:=20 [FlyRotary] Fwd: Fuel injector pump=20 cooling??

 


Anyone = see any=20 issues with one of the automotive in-tank pumps being used outside the = tank?=20 Looking at the overall pump/pickup/regulator/level sensor/etc = assemblies in=20 most auto fuel tanks, it would appear that the pump itself would be = above the=20 level of the fuel anyway if the tank is less than 1/4 = full.

I've been=20 looking for a Facet transfer pump that has both a backflow valve & = an=20 anti-siphon valve (40257 is one) but they are very hard to find &=20 expensive when you find them. During my search, I ran across=20 this:
http://www.amazon.com/gp/product/B000BMBSS0/ref=3D= pd_lpo_k2_dp_sr_3?pf_rd_p=3D486539851&pf_rd_s=3Dlpo-top-stripe-1&= pf_rd_t=3D201&pf_rd_i=3DB002YP4Q3Q&pf_rd_m=3DATVPDKIKX0DER&pf= _rd_r=3D1JFK34G48EBF5R93EB2Y

The=20 application appears to be 87-98 GM products.

It appears to be = very=20 similar to the 'standard' in-line pump that Tracy supplies, with the = exception=20 of plastic components in the output end. Assuming that it's a positive = displacement gear pump, it should supply both the backflow & = anti-siphon=20 features I desire & at roughly $30 shipped, it's cheaper than even = the=20 cheapest Facet 'solid state' transfer pumps. I'm hoping that = cooling/lube=20 won't be an issue as long as it isn't run 'dry' for more than a few = seconds at=20 the end of a transfer=20 cycle.

Charlie


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