[richardk]

Something is draining the battery in my '67 GTO. I'm reasonably familiar with electrical circuits but I'm definitely not an electrician.

With everything shut off, the neg. cable off the battery and a meter between the cable and battery post I show full battery voltage. I've recently done some electrical work so I looked there first but unhooking that stuff made no difference. I next disconnected the hot wire from the back of the alternator and the draw dropped from 12.7 volts down to about 5.5. As I held the probes in place that number kept dropping at the rate of a tenth of a volt about every 10 or 15 seconds until I got tired of watching it at around 3.8 volts.

And that's as far as I got today. I recently had surgery on my right hand so I'm doing all this mostly one handed which slows things down considerably.

Any thoughts... alternator? Voltage regulator (external)? Next steps? I would appreciate any advice on what to do next. Thanks in advance.