Join Date: May 2002
Location: Kingsland, Georgia
Blk69, To clarify what ScottB is saying the battery drain test is done with the engine off and you use the ground side of the battery with a test light. Stick the point in the negative post and alligator clip on the ground cable (disconnected from battery). If there is a draw the test light will light up. If your test light doesn't light up, turn something on in the car to verify you are hooked up correctly.
The best way to test your battery is to have it load tested. We use a Sun VAT tester which is real nice and is all electronic. Capable of load testing the battery, checking the alternator on the car with the engine running, and starter testing. Checks the amperage output of the alternator which is really what you want to know and also checks the diodes in the alternator.
It is possible for a bad alternator to drain a battery down with the car sitting/engine off.
Going back to the test light for a drain on the battery. You may get a dim test light if you have a radio in the car that has a power wire for "memory" (station presets, clock, etc.). Shouldn't cause a dead battery sitting for a week, but could say sitting for a month.
I would first check for a draw, then get the battery tested, last thing, look at the alternator/voltage regulator.
69' X-11 350, Turbo 350, Factory Air, PS, PB, 12 Bolt (410 gear) & NOT AN SS