flyrotary@lancaironline.net Mailing List Archive

Mark, When you say the EM2 doesn't like it that high - isn't that because of a warning limit you have set in it? Or have left it at a default setting? I agree that if the fuel pressure should suddenly start showing higher readings it could possibly indicate something like blockage in fuel return from the pressure regulator or a filter getting plugged up, etc. So its nice to have a warning on the high end.

But, I find it difficult to believe that Tracy hard coded in a pressure of 41 psi. But 41 psi at high power setting and 35 at idle also seem quite in the ball park.

----- Original Message -----

From: Mark Steitle

To: Rotary motors in aircraft

Sent: Sunday, June 03, 2007 8:02 PM

Subject: [FlyRotary] Re: MAP Referenced Fuel Pressure Regulator

Ed,

Yes, 41 sounds reasonable, except the EM-2 doesn't like it that high. It flashes until the engine is started and the fp drops. I adjusted my static fuel pressure up to 41 psi today. That initial setting now gives approx. 34psi at idle.  FWIW

Thanks,

Mark

On 6/3/07, Ed Anderson <eanderson@carolina.rr.com> wrote:

Hi Mark,

Yes, I can tell you, but doubt it will be too meaningful.

My regulator does have a reference to the manifold - but, this apparently only causes the pressure regulator to react to positive (boost) manifold pressure - in otherwords while under boost pressures the regulator will increase fuel flow to the injectors by increasing pressure. It apparently does not regulate the fuel pressure at normal manifold pressure ranges.

But, in any case my pressure regulator keeps the fuel pressure at 41 psi with one pump on and it increases to 43 with both pumps on. Again,changing manifold pressure does not affect my fuel pressure.

I intend to swap it out (someday) for one that is a true manifold referenced regulator - but, sigh, just always seems to be something else to do - and it has worked for me for 10 years. But, I could probably get an even smoother idle if I swapped it out.

  I would say 41-43 psi would be a reasonable setting.

Ed

----- Original Message -----

From: Mark Steitle

To: Rotary motors in aircraft

Sent: Saturday, June 02, 2007 8:25 PM

Subject: [FlyRotary] MAP Referenced Fuel Pressure Regulator

Ed,

Can you tell me what pressures you're seeing on your fuel pressure at idle, mid-range, and WOT? Also, please verify that you set the fuel pressure with engine stopped and fuel pumps ON. What should the fuel initial fuel pressure be set at for our purposes?

Thanks,
Mark S.