Quote Originally Posted by DennyW View Post
Take off the battery negative cable.
Then, try the battery charger again. Does it still spark when touching the pos cable of the charger to the battery ?

ps:
https://www.wikihow.com/Find-a-Parasitic-Battery-Drain
It didn't spark with the negative battery cable disconnected. Then again it didn't spark later with both cables connected. Sounds like the capacitor charging is what was happening (it's an old charger). I never experienced that before and it surprised me.

I need to get a better meter to search for the draw. Thanks for the link.