Tracy, UMA has some fuel pressure transducers - I've used
the same one for over 10 years. Look under the non-TSO Pressure sensors
menu. I use the one with a range of 0-70 psi with Pressure max of 290
psi.
Ed
Sent: Tuesday, December 28, 2010 5:26 PM
Subject: [FlyRotary] Re: Fuel rail pressure
That sensor comes with a tag warning NOT to use for fuel pressure
applications.
Tracy
On Tue, Dec 28, 2010 at 5:11 PM, Chris Barber <cbarber@texasattorney.net>
wrote:
So, this http://www.egauges.com/vdo_send.asp?Sender=100PSI_VDO is
not suitable? I thought this is where you mention in the
manual. I did not see a fuel disclaimer and I think I got to the link
from the fuel link.
Chris
Sent: Tuesday,
December 28, 2010 3:51 PM
To: Rotary motors in aircraft Subject:
[FlyRotary] Re: Fuel rail pressure
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 states 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 <bhughes@qnsi.net> 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 that this assumes that your EM2 has
been updated since this change was developed (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 are 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 the 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 is 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 – 6.922 , LOW END OFFSET – 0, SENSOR
OFFSET ~ 963 , LOW ALARM LIMIT - ~28 , HIGH ALARM LIMIT -~55.
Tracy
On Tue, Dec 28, 2010 at 12:10 AM, <bktrub@aol.com> wrote:
Tracy,
did you ever find a suitable replacement fuel pressure sender? What
are you using now?
Thanks,
Brian Trubee
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 20B installation so there is no
fuel flow to flush vapor from the rails on hot startups. This
arrangement is now used on most new cars. Even with this 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 advantage other than being much easier to
calibrate. Tracy
On Mon, Dec 27, 2010 at 6:53 PM, <bktrub@aol.com> 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 in such a case would cause coller fuel to flow through the rail and
back to the tank.
Brian Trubee
-----Original
Message----- From: Al Gietzen < ALVentures@cox.net> To: Rotary motors in
aircraft < flyrotary@lancaironline.net> 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 you 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’s true even if you call
the e-shaft a crankshaftJ.
Al
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