rleffler
Well Known Member
As several already are aware, I had some fuel flow issues on my first flight. At the time, in the air, I wasn?t quite sure what the issue may have been. It was initially looking like a blocked fuel line. The symptom was that the fuel pressure dropped significantly, but came back up with the electric fuel pump turned on and switching the tanks. I promptly landed and started looking for the root cause.
1. The left and right tank fuel flow (measured at the firewall, forward of the filter and pump) was 58 gallons/hour. Rules out a blockage aft of the firewall.
2. The fuel vents are not obstructed
I ran the engine in a static test. Was getting about 20psi on the engine fuel pump and about 26psi with the electric fuel pump enabled. Since this is all within specifications, this is the worst of all the scenarios. No root cause and everything seems to be working as designed.
This morning I flew for about an hour on flight #2.
When I turned off the electric fuel pump, fuel pressure started to immediately drop. I let it drop to about 10psi before I re-engaged the electric fuel pump. With the electric fuel pump running, I was getting 26psi. I repeated this scenario multiple times on both fuel tanks during the flight. Results were pretty consistent.
It?s looking like I may have a bad fuel pump on this 1 SNEW YIO-540-D4A5. I plan on giving Lycoming a call in the morning.
My questions is there any other scenarios that I?m overlooking that may yield similar symptoms?
Thanks,
bob
1. The left and right tank fuel flow (measured at the firewall, forward of the filter and pump) was 58 gallons/hour. Rules out a blockage aft of the firewall.
2. The fuel vents are not obstructed
I ran the engine in a static test. Was getting about 20psi on the engine fuel pump and about 26psi with the electric fuel pump enabled. Since this is all within specifications, this is the worst of all the scenarios. No root cause and everything seems to be working as designed.
This morning I flew for about an hour on flight #2.
When I turned off the electric fuel pump, fuel pressure started to immediately drop. I let it drop to about 10psi before I re-engaged the electric fuel pump. With the electric fuel pump running, I was getting 26psi. I repeated this scenario multiple times on both fuel tanks during the flight. Results were pretty consistent.
It?s looking like I may have a bad fuel pump on this 1 SNEW YIO-540-D4A5. I plan on giving Lycoming a call in the morning.
My questions is there any other scenarios that I?m overlooking that may yield similar symptoms?
Thanks,
bob