Aug 14, 2011 · Lycoming O-360-A1A engine driven fuel pump question: How much fuel should be flowing from the outflow end of the pump? I am chasing a possible fuel restriction and when we disconnect the hose from the discharge side, it is a weak flow at best. Certainly not race horse flow as would be expected. Different airplane, same set up and similar results.

May 10, 2012 · I have had two engine driven fuel pumps on my engine in the last 700hrs. Both wobble pumps. The first one failed in the mechanism (not the normal gasket). Normally the fuel pressure is steady, but I noticed that both old and new pump occasionally fluctuate between about 23 (or 25) and 27 PSI.

Nov 21, 2006 · If the fuel system cannot deliver this flow rate, presumably at any fuel level (full or empty), an engine driven fuel pump is required. And in case of failure of that fuel pump, a boost pump is therefor also required. I was told that the fuel line size was the limiting factor in the C150/150 & C170/180 conversions.

Mar 13, 2015 · FWIW I believe that the FAA's policy with certificated airplanes is that if you have an engine-driven fuel pump, you also have an electric boost pump for backup. My C150/150TD had a Lyc 320-E2A engine, and in spite of it being a high-win with gravity fuel feed it had an engine-driven pump and an electric boost pump.

Aug 4, 2017 · The electric pump did seem to stabilize things when in flight, but I didn't do a lot of troubleshooting in flight. When attempting takeoff I did not switch the boost pump on/off during ground roll and aborted fairly quickly. I can go out and try cycling the throttle with the boost pump on and engine off to see what happens.

Apr 24, 2010 · If you were to lose your engine driven fuel pump, you'd have to rely on the emergency side of the pump switch, and there is a high probability that the pump will overheat fairly quickly at that speed. Having lost an engine driven pump while I was approximately 20 miles from shore over cold water, I can testify that this is an important check.

Jun 1, 2021 · The engine driven and electric backup fuel pumps on most of the 170 to O-360 engine conversions are required to provide sufficient fuel to the (more powerful) O-360 engine. Thirty five (or more) more HP requires more fuel.

Jul 12, 2015 · The engine driven fuel pump combined with a full rich default would complete the non electrical failure mode. SDS/Fly EFII's solution to redundancy is dual ECUs, basically two independent systems, but it all runs on electrons bumping each other.

Feb 12, 2018 · It has an engine driven fuel pump which normally puts out about 2 1/2 psi, whereas the electric pump puts out around 4 psi. So far, the only extra "maintenance" my fuel system has ever required in the almost 16 years I've had the airplane was not maintenance at all, but converting the glass gascolator bowl to an aluminum Steve's Gascolator.

May 31, 2006 · If I ran the electric pump the flow would indicate higher and EGT would cool another 100 degrees! I tried adjusting the high side of the engine driven pump but that only barely changed the flow. It ended up being a dirty screen. The one that screws into your fuel control unit.