intermitant charging problem
I have a 1975 230 gas engine. I put a knew battery when i bought the car 2 yrs ago. Also replaced the alternater at the same time. soon after about 6 months charging problem again took it and had it tested to only be charging at 12 volts. so I replaced it again .Then all was fine charging at over 13voltstil resently seems the battery light flickers on and light s dim, then after the car sits a few hours itneeds a jump. funny thing is it never happens to me, three different times ive had the car for two weeks a stretch, with out incident, my daughter takes the car back to college and soon within days calls me with a dead battery.I know she isnt leaving anything on to drain battery, I guess i'm hoping someone has heard of a simular problem and knows of an easy fix.