1993 caprice electrical problem

[sd402]

I am having a problem with my 1993 caprice. I bost it to get going, the alt is charging and it runs fine no warning lights or odd guage readings. I turn off the car an it will restart with no problem but if I leave it for a few hours the batt. goes dead. the battery is new and so is the alternator. No lights are left on or anything. befor it took a few days till the batt was dead and now its a few hours or less when its cold out. I have no idea what it could be. I have pulled all fuses and so fourth and still the batt dies out. Its not the batt as I said, and its charging fine. Any ideas as to what this could be? Any help would be much appretiated.