Exploding voltage regulators

Help.....Ive recently helped a friend with a S6 to 360 conversion. We first tried a new powermaster alternator that had two field connections. We grounded one and landed the green wire to the other. Once fired, it put out 18 volts and melted a lead in the old voltage regulator....at the same time, I believe, we stressed the electrical wiring.

Anyway we figured the new alt was to much so we changed back to the original alt with one field wire. We had noticed that we melted the green wire insulation from the reg to the alt and also the blu wire from the resistor to the reg. We replaced these wires and checked out the other wires in the same harness. They looked OK. At the time we didn't know it but we had problems under the dash as well.

Anyway, we installed another regulator and fired up the car....using the voltmeter across the battery terminals we measured 13.4 at about 2000 RPMS and as we increased the RPM's the voltmeter reading increased as well.

Around 14.4 volts we heard a loud POP and the voltage reading dropped to 12 indicating we had lost the field current to the alt. Also we had noticed the radio came on when the heater switch was turned on and the winshield wipers would not turn off no matter what position the switch was in.

We figured there was a short under the dash so we got into the wiring harness and sure enough...black melted to red and a few other colors in the mix as well.....explained the strange switch/radio problems. So we replace the melted ammeter wires all the way to the bulkhead connector and even removed it and checked to see if we had cross terminals due to the extreme heat melting them a bit.

Seemed ok so we started the car without a regulator as we had exhaused our supply and it fired right up all systems worked again normaly..except charge of course but we figured when we got and installed the new voltage regulator it would be fine......WRONG....we installed the new voltage regulator and we are still on the stock 1 field wired alternator which we brought in for testing and checked out OK.

We turned the key and a cloud of smoke came out of the voltage regulator and the wires got hot. Pulled off teh blue wire quyickly and pulled the bat cable as well......checked the wires and didn't see anything but now it wont even start.

What should I be looking for and what would explode regulators like that?

Author: admin