I am having problems with low fuel pressure with the engine driven fuel pump
It will run fine for a while maybe an hour or two at 28 psi but every now and then the pressure will drop to around five or six psi turning the electric fuel pump on brings the pressure right back to 28 psi
I sent the engine driven fuel pump back to the manufacture they ran it on the bench could not duplicate installed another engine driven fuel pump from them same problem Checked the fuel lines from the tank to the engine for leaks no leaks no leaks are around the engine driven fuel pump I am thinking when the fuel is low ram air from the fuel vent is letting high-pressure air in the tanks and then being sucked up by the fuel lines and cavitating the engine driven fuel pump this is just a guess
I say this because the engine driven fuel pump works fine on the ground
It will run fine for a while maybe an hour or two at 28 psi but every now and then the pressure will drop to around five or six psi turning the electric fuel pump on brings the pressure right back to 28 psi
I sent the engine driven fuel pump back to the manufacture they ran it on the bench could not duplicate installed another engine driven fuel pump from them same problem Checked the fuel lines from the tank to the engine for leaks no leaks no leaks are around the engine driven fuel pump I am thinking when the fuel is low ram air from the fuel vent is letting high-pressure air in the tanks and then being sucked up by the fuel lines and cavitating the engine driven fuel pump this is just a guess
I say this because the engine driven fuel pump works fine on the ground