X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-wy0-f180.google.com ([74.125.82.180] verified) by logan.com (CommuniGate Pro SMTP 5.3.11) with ESMTP id 4657018 for flyrotary@lancaironline.net; Tue, 28 Dec 2010 16:52:30 -0500 Received-SPF: pass receiver=logan.com; client-ip=74.125.82.180; envelope-from=rwstracy@gmail.com Received: by wyb28 with SMTP id 28so9535603wyb.25 for ; Tue, 28 Dec 2010 13:51:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:sender:received :in-reply-to:references:date:x-google-sender-auth:message-id:subject :from:to:content-type; bh=1CnxH6XN6u+QglT2fMPC34FqkegSqJ/hDRhods1jMhk=; b=c+pVgt+IVNeKnIhDARuJTE/R5dc7wY6n3yfgz+A32fshdGCImzINlsc5WSAGKUEE1v ls4z2JeUEMJW5pgHyyaIwGJiuKKlCgsibP7syCId8juWdPfDPda07jY4tAFrk+5TyKUF c7D8n7cxQBVE7vDUBImGWnHYs4ubIPOz4KZGg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=R+ehDbPyc9zGs13IsNe125mgwinPUnBNzNbQzech3JS05qtagkyXPcQKw5jTvuXu7r O/+U1myvrzCt0K1bh/mlfBddnnq0RXPX9ACA616hNMPWfDQSHb8cym+Inr/TANB8Odcw EFDlasv0tLXD/ao3ZgoZmwT3Jgke6yqy074Us= MIME-Version: 1.0 Received: by 10.216.174.65 with SMTP id w43mr17351282wel.95.1293573114548; Tue, 28 Dec 2010 13:51:54 -0800 (PST) Sender: rwstracy@gmail.com Received: by 10.216.200.158 with HTTP; Tue, 28 Dec 2010 13:51:54 -0800 (PST) In-Reply-To: References: Date: Tue, 28 Dec 2010 16:51:54 -0500 X-Google-Sender-Auth: Y4ZpdGeRU8mwYrcaSzRyWuIeG0I Message-ID: Subject: Re: [FlyRotary] Re: Fuel rail pressure From: Tracy To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=001485f1d876fbd29704987f753a --001485f1d876fbd29704987f753a Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable *My Advanced Flight System EFIS \ EM shipped with a Stewart Warner fuel pressure sensor. They have had a few failures and now ship with VDO. Go figure.* Strange indeed. I can't find a listing anywhere for a VDO electric fuel pressure gauge nor can I find a VDO pressure sensor that specifically state= s that it is rated for fuel pressure use. The ones I found now state that they are NOT rated for fuel. Got a part number for it? Tracy On Tue, Dec 28, 2010 at 3:35 PM, Bobby J. Hughes wrote: > Tracy, > > My Advanced Flight System EFIS \ EM shipped with a Stewart Warner fuel > pressure sensor. They have had a few failures and now ship with VDO. Go > figure. > > Bobby > ------------------------------ > *From:* Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] *= On > Behalf Of *Tracy > *Sent:* Tuesday, December 28, 2010 1:40 PM > *To:* Rotary motors in aircraft > *Subject:* [FlyRotary] Re: Fuel rail pressure > > Hello Brian, > Here is an excerpt from the updated EM2 installation guide. Note tha= t > this assumes that your EM2 has been updated since this change was develop= ed > (last 2 months or so). > > FUEL PRESSURE SENSOR > > The EM2 was originally designed around VDO pressure sensors and the > fuel pressure sensor was to be the same type as used for the Oil Pressure > sensor. VDO at some point changed the design of these sensor and they ar= e > no longer safe to use with Fuel (they begin leaking from the terminal > end). The closest substitute is a Stewart Warner 114875. > These are available from > Summit Racing as PN *SWW-114875. **To make it fully compatible with th= e > EM2 you must wire a 562 ohm resistor from the sensor output terminal to > ground. This can be added near the sensor or near the EM2, which ever i= s > most convenient. You must also set the Channel 13(mixture) Low limit > value to 1 instead of 0. The calibration values for the Fuel pressure > channel (12) should then be set to the following values: Scale factor = =96 > 6.922 , LOW END OFFSET =96 0, SENSOR OFFSET ~ 963 , LOW ALARM LIMIT - ~28= , > HIGH ALARM LIMIT -~55. * > > Tracy > > On Tue, Dec 28, 2010 at 12:10 AM, wrote: > >> Tracy, >> did you ever find a suitable replacement fuel pressure sender? What are >> you using now? >> >> Thanks, >> Brian Trubee >> >> >> >> -----Original Message----- >> From: Tracy >> To: Rotary motors in aircraft >> Sent: Mon, Dec 27, 2010 4:30 pm >> Subject: [FlyRotary] Re: Fuel rail pressure >> >> Just for another data point: >> >> I installed the fuel pressure regulator prior to the fuel rails in my 20= B >> installation so there is no fuel flow to flush vapor from the rails on h= ot >> startups. This arrangement is now used on most new cars. Even with thi= s >> arrangement I have had no trouble with vapor lock. Even if it should >> happen, the EC2/3 primer function would be able to vent the vapor from = the >> rails. >> >> This setup allows the use of a Floscan type fuel flow sensor with the >> EM2/3 since there is no return flow from the fuel rails. No big advanta= ge >> other than being much easier to calibrate. >> >> Tracy >> >> On Mon, Dec 27, 2010 at 6:53 PM, wrote: >> >>> It seems to me that the fuel would have to be pretty hot for the vapor >>> pressure to exceed 40 psi and cause vapor lock. Running the fuel pump i= n >>> such a case would cause coller fuel to flow through the rail and back t= o the >>> tank. >>> >>> Brian Trubee >>> >>> >>> >>> -----Original Message----- >>> From: Al Gietzen >>> To: Rotary motors in aircraft >>> Sent: Mon, Dec 27, 2010 3:49 pm >>> Subject: [FlyRotary] Fuel rail pressure >>> >>> >>> Also remember that when you are starting the engine you are starting it >>> under a load. This is different then in a car config where in a car yo= u are >>> starting it with no load attached to the crankshaft. If the fuel rails= are >>> getting so hot that they are vaporizing I would think this would cause = an >>> excess pressure in the fuel system and be very dangerous. This is not = a >>> problem I have ever had in a car. What is causing this besides poor >>> ventilation? >>> The pressure in the fuel rail can never exceed the setting of the >>> pressure regulator; which should bear about 40 psi engine off. That=92s= true >>> even if you call the e-shaft a crankshaftJ. >>> Al >>> >>> >> >> > --001485f1d876fbd29704987f753a Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable My Advanced Flig= ht System EFIS \ EM shipped with a Stewart=20 Warner=A0fuel pressure sensor.=A0=A0They have had a few failures and=20 now ship with VDO. Go figure.

Strange indeed.=A0 I= can't find a listing anywhere for a VDO electric fuel pressure gauge n= or can I find a VDO pressure sensor that specifically states that it is rat= ed for fuel pressure use.=A0 The ones I found now state that they are NOT r= ated for fuel.=A0 Got a part number for it?

Tracy

On Tue, Dec 28, 2010 at 3:35 PM= , Bobby J. Hughes <bhughes@qnsi.net> wrote:
Tracy,
=A0
My Advanced Flight System EFIS \ EM shipped with a Stewart=20 Warner=A0fuel pressure sensor.=A0=A0They have had a few failures and=20 now ship with VDO. Go figure.
=A0
Bobby
From: Rotary motors in=20 aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of=20 Tracy
Sent: Tuesday, December 28, 2010 1:40 PM
To:= =20 Rotary motors in aircraft
Subject: [FlyRotary] Re: Fuel rail=20 pressure

Hello Brian,
=A0=A0 Here is an excerpt from the updated EM2= =20 installation guide.=A0=A0 Note that this assumes that your EM2 has been=20 updated since this change was developed (last 2 months or so).

FUEL PRESSURE=20 SENSOR

=A0=A0=A0=20 The EM2 was originally designed around VDO pressure sensors and the = fuel=20 pressure sensor was to be the same type as used for the Oil Pressure=20 sensor.=A0 VDO at some point changed the design of these senso= r=20 and they are no longer=A0 safe to use with Fuel (they begin=20 leaking from the terminal end).=A0=A0 The closest substitute= =20 is a Stewart Warner=A0=20 114875.=A0=A0=A0=A0=A0 These are=20 available from Summit Racing as PN=A0=20 SWW-114875.=A0=A0 To make it fully compatible with the EM2 you must=20 wire a 562 ohm resistor from the sensor output terminal to=20 ground.=A0=A0 This can be added near the sensor or near the=20 EM2, which ever is most convenient.=A0=A0=A0 You must also=20 set the Channel 13(mixture)=A0 Low limit value to 1 instead of= =20 0.=A0 The calibration values for the Fuel pressure channel (12= )=20 should then be set to the following values:=A0 Scale factor = =96=20 6.922 , LOW END OFFSET =96 0, SENSOR OFFSET ~ 963 , LOW ALARM LIMIT - ~28 ,= HIGH=20 ALARM LIMIT -~55.


Tracy

On Tue, Dec 28, 2010 at 12:10 AM, <bktrub@aol.com<= /a>> wrote:
Tracy,
did you ever find a suitable replacement fuel pressure sender? What = are=20 you using now?
=A0
Thanks,
Brian Trubee



Sent: Mon, Dec 27, 2010 4:30 pm
Subject: [FlyRotary] Re: Fuel=20 rail pressure

Just for another data point:

I installed the fuel pressure=20 regulator prior to the fuel rails in my 20B installation so there is no f= uel=20 flow to flush vapor from the rails on hot startups.=A0 This arrangement i= s=20 now used on most new cars.=A0 Even with this arrangement I have had no=20 trouble with vapor lock.=A0=A0 Even if it should happen, the EC2/3=A0=20 primer function would be able to vent the vapor from the rails.

Th= is=20 setup allows the use of a Floscan type fuel flow sensor with the EM2/3 si= nce=20 there is no return flow from the fuel rails.=A0 No big advantage other th= an=20 being much easier to calibrate.

Tracy

On Mon, Dec 27, 2010 at 6:53 PM, <bktrub@aol.com= >=20 wrote:
It seems to me that the fuel would have to be pretty hot for the v= apor=20 pressure to exceed 40 psi and cause vapor lock. Running the fuel pump i= n=20 such a case would cause coller fuel to flow through the rail and back t= o the=20 tank.
=A0
Brian Trubee



-----Original=20 Message-----
From: Al Gietzen <ALVentures@cox.net>
To: Rotary motors in ai= rcraft=20 <fl= yrotary@lancaironline.net>
Sent: Mon, Dec 27, 2010=20 3:49 pm
Subject: [FlyRotary] Fuel rail pressure

=A0
Also remember that when you are starting the engine= =20 you are starting it under a load. =A0This is different then in a car=20 config where in a car you are starting it with no load attached to the= =20 crankshaft. =A0If the fuel rails are getting so hot that they are=20 vaporizing I would think this would cause an excess pressure in the fue= l=20 system and be very dangerous. =A0This is not a problem I have ever had = in=20 a car. =A0What is causing this besides poor=20 ventilation?
The pressure in=20 the fuel rail can never exceed the setting of the pressure regulator; w= hich=20 should bear about 40 psi engine off. That=92s true even if you call the= =20 e-shaft a crankshaftJ<= span style=3D"font-family: Verdana; color: blue; font-size: 11pt;">.=
Al
= =A0



--001485f1d876fbd29704987f753a--