New battery losing charge 1963 Thunderbird

[Lizzy]

The new battery in my 63 t-Bird loses its charge when parked for a few weeks.It is disconnected.Could it be that the alternator is not keeping it charged up when I drive it or could it be the regulator which is also new.Any ideas??

 

[Bond007]

Definitely have the alternator checked. It’s also possible that the battery had a defect even though it’s new. Most big auto parts stores will check the alternator output for free.

 

[Hadderz]

You mentioned ''it is disconnected'', if so then the battery is duff! It should not discharge by itself in a short period of time.