I know this is for Abody cars but i have a 1982 dodge d150 that recently starting over charging . i have an after market battery volt guage with needle . before the truck started over charging it stayed at 14 volts . when it over charged it pegged out all the way over to 16. When i bought the truck it had wiring issues . i went through and properly fixed all issues including adding extra ground wires : cab to frame, cab to engine, battery ground to block as suppost to be and added a ground wire from battery to to inner fender/radiator support. I've already checked fusable links so on and so on. I found that the voltage regulator was bad ! The factory mount spot is on the fire wall up above the distributor then just to the left . evidently water ran down and some how made it past the factory epoxy on the back of the voltage regulator? It doesnt surprise me since it cam from O'really auto parts stamped CHINA . Anyway i replaced the regulator and added some spacing between the regulator and the fire wall and had the alternator tested all is good . but 2 things : 1 it is now at idle fully warmed up its charging at 14.64 volts . is that good? Second i heated up the back of the old regulator and popped the chunks of epoxy off to find it filled with really fine white sand that had gotten rust in it and shorted out one of the soldered inner field wires. What is the sand about ? I had 2 other old non work regulators different brands that i tore apart and they had sand in them as well ????