Dives into dusty ole drawer and finds BE-58 POH - 1972 series......
"Aux Fuel Pumps;
An individual two-speed electric aux fuel boost pump is provided for each engine.HIGH press. OFF, or LOW press is selected with each aux fuel pump switch on the pilot's sub-panel.
HIGH press is used for stablizing the fuel press before starting and provides near max engine performance should the engine-driven pump fail.
In high ambient temps, LOW press should be used for ground ops, take-off, and climb.
The location of the aux fuel pumps in the system permits fuel to be drawn from any cell within the system by the pump for the operating engine.
The HIGH position should not be selected while the engine is operating except in the event of engine driven pump failure since the HIGH press mode supplies a greater pressure than can be accepted by the injector system for a reduced power condition."
That's all it says folks.
Page 6-17 in my Beech POH.
The Emergency Procs for crossfeed talk about Aux fuel pump - LOW or OFF as req'd.
Page 3-8
Doesn't really answer yr query I know, but that is all the 'good book' says.....
Re your 'turns out something unrelated' comment....care to elaborate?
Not wishing to guess anything 'evil'....just curious is all.....
Cheers
