06 5.9 cummins won't start

[SxvxgeSerg]

so i just recently picked up a 06 2500 5.9 6speed mega cab 130k miles
it said it runs and drives but when it got delivered
batteries where both 0%

charged them up
had the block heater on too
engine almost start cranks really good but now the batteries are dead again charging over night

I know the truck has been sitting for 3 months in the winter

I have never owned a diesel what should i do to get it running?
what are things i need to know owning a diesel/mainteince?

was thinking of draining the fuel and go from there

thanks so much

 

[SxvxgeSerg]

here's a pic of the beast

 

[Badger 13]

I would check the batteries for the first thing. Don't know what your outside temp is, or how old the batteries are. I'm sure you waited for the "wait to start light" went out so the grid heaters did their job..