fuel psi drop

[yarddart]

RV8 io-360 -170hrs - bendix airflow- changed fuel pump - changed dynon inducer FF. no leaks 28PSI then drops to 21PSI what do you think?cell 1630 816 8825 Thanks Steve

[Kevin Horton]

More info please. Is this on the ground, or in flight? Electric pump ON or OFF? After a cold start, or a hot start? Is it a sudden pressure drop, or gradual? What rpm, mp, altitude and OAT? etc.

[Russ McCutcheon]

Hi Steve,

I have an IO-360 angle valve with Bendix FI, I have not had it from new so I don?t know if it was ever any different and I don?t know much about how it works either. My fuel pressure is, idle around 18 give or take, cruse at 2450 rpm 24 psi, and full power full rich 2750 rpm 21 to 22 psi This setting flows 20+ GPH at about 150 to 200 degrees ROP. The engine runs perfict and I have never seen the fuel pressure above 25 psi, normaly it?s never above 24. My backup fuel pump is operated by hand (Christen manual pump/fuel selector valve/filter unit) so all my figures are only with the engine driven pump operating. I don?t know any thing about this just thought you might like to see the comparison between yours and one similar.

[sf3543]

I have an IO-360 Parallel valve with the same FI set up.
The engine driven fuel pump provides about 21-23 PSI but with the electric pump on, it jumps to 28 PSI.
I believe this is normal.