Parasitic battery drain?

Hi all,

My '65 A-100 somehow drains the battery if it sits more than a day. I will measure the current tomorrow, but it's enough to drain a new battery in about 20 hours. Are there any common points where a sort occurs or something else that could be doing this?

Thanks!!

is it pretty stock setup or you have alot of custom mods ? once your set up to measure the draw , you can start pulln fuses and unpluggin stuff to isolate where its goin . check alt and reg also if you have electronic ign , I have seen a bad module cause a draw . not tryn to insult you but take a walk around the rig and make sure you dont have a problem w/brake lights stickin on ,had that problem myself not too long ago

It's totally stock. No fancy ignition or anything like that. I, too, was sure there was a light that wouldn't turn off or something like that. Can't find anything, though. To drain a battery like that it's gotta be a 2 or 3 amp draw, yes?

Donni's got you covered. I prefer to use an old seat belt buzzer on cars, since the battery is under the hood and it's easier to hear than to make a change then look.
On our vans, you are right there next to the battery so a light is fine.
since this is happening with the key off, concentrate on the stuff that is always powered, not switched. Common stuff is radio memory, a charging system regulator that doesn't shut off, brake lights, horn and interior light circuit that's shorted. Grab a copy of the wiring diagram, hook up the test light as shown, then start disconnecting stuff one at a time.
Also unplug the ignition switch at some point. I've seen them sometimes feed power when off.
This is one of the tough things to track down, so take your time and remember that vans are simple!

Seems like the ignition switch. Sometimes with the key at 12 o'clock and removed the ignition is still live, other times it stays "live". I guess I will replace the switch.

Or, as I meant to say, sometimes it is off.