1977 nova car help

i have been having this problem with my car...
the battery is contantly out of power, so i must recharge it (i even bought a new battery, so that isnt it)
after i recharge the battery, the engine works fine, but when i turn it off, and leave it sitting there, it loses its power, and a day later its completely out again.
i dont THINK it is the alternator, because it does drive, and an engine would supposedly need to have a working alternator to continue working right??
well, thats my problem...anyone know what to do??

The engine will run with a faulty alternator since you are charging the battery off line, but the battery will drain down as you drive until it won't have enough power for lights, etc. and eventually ignition. Take your alternator to a parts store and have them check it's output on a machine. If the alternator is good and the battery is being drained at night while the car is off, try leaving the battery disconnected when the car isn't running. If this eliminates the problem then you need to find out what's causing the battery drain.

Let us know how it goes and welcome aboard! :wave:

almoststock is right take it to the auto parts shop and have them test it