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Now that I am on my 3rd flight into Phase I on my UL350i Cruzer I noticed that my fuel psi is below min. I am only getting 29 psi in flight. I am using a Skytek header tank like David Beaulieu--he is getting the numbers advertised by UL. I used 1/2" fuel lines from the tanks to the Skytek then 3/8" from the header to the firewall. Am curious as to what others are getting for fuel psi.
My fuel pressure maintains a fairly constant 43-44 psi with either pump. I don’t have a header tank and my supply lines are 3/8 id. I have a 350is in my stol 750 with100 hours on it. I think I would be talking to UL if I were you, as 29 is low.
Just curious if your fuel pressure is good before you start your engine, if so, does it drop at idle or under power? Also, your FADEC should be switching pumps if the main one is not holding pressure - have you tried manually switching pumps? Several questions on why you are getting low readings, but if the engine was performing correctly with the first 3 flights, I would start by checking with a different fuel pressure tester. Just my thoughts....
Hey guys thanks for the suggestions and advice. Very much appreciated. I did call Ray at UL and told him my story. He pretty much knew exactly what the problem was. He told me to go to the sensor mapping page on my Skyview and check to see what flavor of Kavlico sensor was being used for fuel pressure. I saw that it was the Kavlico 50 psi sensor but remembered that I had actually ordered the 75psi version. I changed the value and then tried both pumps and voila--I was getting 42 psi!
I think that crisis has been averted. Thanks again guys for helping out!