[olddog]

The power coming out of the alternator is AC with a crude rectifier, giving a DC current with a lot of AC ripple. The voltage regulator is basically a fast acting switch that is turning the power off and on to clip the DC voltage off before it goes too high. I would not recommend connecting the fuel pump to the alternator. DC motors do not like AC power.

The battery is a huge capacitor and filters all the noise out. That is why the alternator is only connected to the battery, and everything else connects to the battery.