Hi all, not a new member justed changed by username/screen name, anyways, i have a 72 charger that has a overcharging problem that i cant figure it out, sometimes the needle on the amp guage is normal and sometimes it spikes way over to the + side. i have a new alt and volt regulator installed and replaced all the wiring and it still does it. this morning it spiked to the + side and stayed there. dont want to start buring wires or overcharge the battey to a point it bursts. I'm not to fimilar with the charging system so any help i would be grateful.

& the times when it is normal (straight up 12 o'clock) that is at a fast idle or higher? If so check (1) reg ground (2) bulkhead (3) part time open (loose connection) somewhere in the field circuit. If not (never steady at 12 o'clock at a fast idle or above w the batt charged) & the reg is grounded good I'd suspect the reg. That is a tough one as you've replaced every (related) component (+ wiring)

How long did it stay pegged to the high side? If the battery is run down it will do that for a short while and then slowly drop back to normal.

at idle is pretty normal, only when the RPMS go up when it swings to the + side and stays there until the RPMS come down.

i dont think its a voltage regulator, i suspect its the in bulk head area

i just drove the car home from lunch and now the needle is pegged all the way to the right and it stays. bad VR?

Bad Voltage Regulator

i just went thru some overcharging issues. my problem was voltage regulator grounding. when the car was repainted it got a lot of paint under the hood. i had to go thru all my grounding and get good clean paintless grounds and added a ground wire to the regulator. so far so good.

..as suggested a poor ground on the volt reg.
check run side of ballast w/key on,engine not running.
if it is less than 11 volts,clean the bulkhead and ignition terminals

make sure the blue wire at the regulator has Batt. voltage,this is the "sensing" wire.I had a Cordoba with and open in the blue wire,and it was full fielding all the time.

be careful.. it will boil the battery and spit acid all over under the hood... i agree bad regulator..make sure grounds are all good and clean

put it on a fast idle & w a jumper wire w alligator clips on each jump from a good ground (fuel line is pretty reliable ground) to the reg case (just scrape the alligator clip on the case) & if you hear the eng speed ch then that is it & what PH said: It's full fielding now & any more than a few seconds (at higher throttle where the ammeter is pegged will fry wires terribly. If you have to drive it I'd unplug the reg as running the batt down a bit is far less problematic than the full fielded overcharging that it is doing now

I had this problem with my 71 Challenger R/T. Would blow the caps off the battery. Literally. I chased it all over. Countless voltage regulators, new alternators, any thing. Had numerous garages look at it. Couldn't find it. One day I was under the dash checking things out and noticed a huge black spot in the connector for the ignition switch to the main harness (at the steering column). Tried to separate them and couldn't. Got to really looking at them and realized it was the heavy hot wire connection that was burned. So I snipped the heavy wires off at both sides of the connector and used a butt connector to put them together. From that point on my alternator charged normally. Never cooked another battery. Car ran better also! Go after and check all connections! Takes time, but it's cheaper.

Have you checked the voltage at the battery or just going by the amp guage ? they are not always rite.. Make sure the vr is grounded good and check the vr plug. I had 1 in a dodge truck that the plug was bad inside the rubber and would cause overcharging.1 battery and 3 vr and that was the probelem. hope this helps ....