Fuel pump setup?

The 914 is an electrically dependent engine. At least one fuel pump needs to be working. One way to approach this is to install the optional belt driven alternator to power the battery bus (and the auxiliary pump) and wire the main pump directly to the flywheel generator, using it only to power the main fuel pump. Now you have three independent power sources: flywheel generator, belt driven alternator, and battery.

Thanks Ken!

The airplane has the belt driven alternator but it was installed later and the electrical configuration of the pumps remained the same, both on the battery bus.  I think I'll be changing the electrical configuration of the pumps to the way you described.      

Hi all

please look at the installation manual.  The pumps need to be split so they get power from 2 sources not one.  Run 1 from BAT buss and the other from your generation source.  If you are not using the onboard generators and only the belt driven one it still works the same.  1 from the BAT and the other from your Alternator.  

The concept is if one source fails the other should still work.  Be sure to run the pumps in series not parallel. 

Cheers