Sounds more like a ground problem. Charge the battery, remove and clean the battery posts and make sure they are tight when you reinstall. Remove the neg cable where it attaches to the block and clean that end then install tight.
If the starter is not aligned correctly, or it it is coming loose,it the bendex could be stuck, when you try to start it the starter solenoid may not be able to pull the bendex resulting in a power draw.