mcurcio1989
Well-Known Member
Airplane is an Aventura 2 (high wing pusher with tank in the bottom of the hull/fuselage) Engine is an O-235-C1B with an L2C accessory case. It has a mechanical fuel pump on the accessory case and the electric fuel pump next to the tank. I take off with the electric on and then shut it off once I'm at 1k feet. Fuel pressure is a steady 4.5psi. It remains a steady 4.5 psi for 30-40 min. Then I will notice it is a little lower and it will sometimes drop to 3 psi and then come back up to 4 and I have seen it get down to 2 as well - at which point I switch the electric on. If I descend for say 20 seconds and then go into a climb for say 10 seconds and then level off and switch the electric pump off the fuel will be at a steady 4.5psi again and remain there for the duration of the flight (all of my flights have been limited to 1 hour thus far).
Question is does this sound like the fuel pump is tired and needs replaced or is it a vapor lock kind of issue?
Is it possible to buy the diaphragms for these? it is a lycoming LW15472 pump. I haven't found them for sale. I hate to buy a new pump for it if I'm not sure that is the problem as they are spendy.
The fuel line runs along side the oil pan mounting flange and it currently does not have fire shield on it (I'm going to add some today). I'm wondering if that may help the problem if it is a vapor lock issue but I won't be able to test fly again for another week or so.
I've only got 6 hours on the engine installation (the accessory case and hence fuel pump has time on it and I don't know how many hours are on the fuel pump). I have been hanging around the airport for my phase 1 with the new engine so the first time it happened I switched the electric pump on and put her down right away. After landing I switched the electric pump off and pressure was fine on the ground while taxiing in. I checked all of my screens (they were clean) and verified the tank vent was clear and facing forward (it was).
Question is does this sound like the fuel pump is tired and needs replaced or is it a vapor lock kind of issue?
Is it possible to buy the diaphragms for these? it is a lycoming LW15472 pump. I haven't found them for sale. I hate to buy a new pump for it if I'm not sure that is the problem as they are spendy.
The fuel line runs along side the oil pan mounting flange and it currently does not have fire shield on it (I'm going to add some today). I'm wondering if that may help the problem if it is a vapor lock issue but I won't be able to test fly again for another week or so.
I've only got 6 hours on the engine installation (the accessory case and hence fuel pump has time on it and I don't know how many hours are on the fuel pump). I have been hanging around the airport for my phase 1 with the new engine so the first time it happened I switched the electric pump on and put her down right away. After landing I switched the electric pump off and pressure was fine on the ground while taxiing in. I checked all of my screens (they were clean) and verified the tank vent was clear and facing forward (it was).
