My brother has a 1982 12a that has no electrical power at all. Already put a optima battery, checked all the fuses and are good, thigth the battery terminals and nothing. Any ideas on what could be wrong? The car was running great 2 days ago.

 

Did you check the 'main' fusible link under the hood? I think it is the middle one on the brown fuse block mounted on the driver side strut tower. not sure if that fuse would kill power to all accesories though, i'm pretty sure it wouldn't. If that's good, I would make sure the battery is grounded well to the chassis.

 

Yea sounds like the Optima fried the links. Did you do ground off pos off (remove) / (install) ground on pos on?

 

after checking the main fusible link(the middle one) check to make sure your negative cable is is grounded properly at the left strut tower and at the bellhousing at one of the trans bolts.