I own a RV7A with an IO-360, fixed pitch prop. with a Dynon SkyView that I bought from the builder and have been having an annoying fuel pressure issue since I bought it. At WOT during takeoff and in a climb with the electric fuel pump on, fuel pressure seems fine (30-35psi) If I shut electric fuel pump off I sometimes get a drop in my fuel pressure and an audio "low fuel pressure" warning from the SkyView. Drops to about 12-14psi. This doesn't happen all the time. When this first happened, I thought it was the mechanical pump, so I replaced it with a new one and checked my filters. That didn?t solve the problem. Engine always runs strong and I haven't had any issues. A week ago, after preheating the engine with a red dragon heater, starting and waiting for oil temps to rise above 100 (OAT was 25F) I performed a run up and I was getting a high fuel pressure warning. I believe it was around 40-45+ PSI. without electric fuel pump on. I waited a while to observe engine performance. All seemed well. I decided to take off and stay in the pattern. After engine warmed to operating temps all seemed fine, fuel pressure came back to normal and I had an uneventful 2 hour flight.
My questions to you all, is: Since I already replaced the mechanical fuel pump, what should I check next? Does temperature effect anything? Why was I getting high fuel pressure in cold weather and low in regular temps? Is it possible my fuel lines are effected by different temperatures? Is it possible it is just a bad sensor? Also, when I turn on my electric fuel pump, according to the SkyView fuel flow goes up a bit. Is this common?
Thanks,
Jim
My questions to you all, is: Since I already replaced the mechanical fuel pump, what should I check next? Does temperature effect anything? Why was I getting high fuel pressure in cold weather and low in regular temps? Is it possible my fuel lines are effected by different temperatures? Is it possible it is just a bad sensor? Also, when I turn on my electric fuel pump, according to the SkyView fuel flow goes up a bit. Is this common?
Thanks,
Jim