battery question

i have a new alternator, new battery,

what could be causing the in-dash voltmeter to be reading just above 8 volts? It varies as well, like down to 8, up to 13, back to 9, all over the board

I assume its the alternator cuz the battery is full, I just charged it for not even 5 minutes. But the alternator is 5 days old :(

Did you unplug the battery when you relaced the alternator? If not it probably spiked the voltage regulator and you'll need a new one.

is ur belt tight enough? did u check ur connections on the alternator n see if u jus dident leave em loose?

Brand new serpertine belt, but loose a loose connection is a possibility.

And yes the battery was unplugged during installation