i have a 1992 chevy blazer .my battery is only showing about half the power .altenator is ok was tested at elec shop.but its not charging battery.the positive battery cable gets so hot you cant touch it .could it be a short or the voltage regulator .any help thanks

 

You may want to start by replacing the positive wire to the alternator. Almost sounds like the wire is broken inside, causing a resistance.

It would not hurt to remove the battery and have it tested.