<VV> Still having electrical problems

[James Cooper]

Hello All,  My '65 Monza sedan is still having an electrical issue and I am checking to see if anyone else has experienced a similar problem.First- thanks for the advice so far!  I have had these issues: 1- Voltage was high in the car at 17.5 volts = Changed the voltage regulator and the voltage dropped to 14.5 volts. 2- Dash lights were very dim = this was indeed the grounding strip under the dash; I checked more carefully and found that it was popped out and not sandwiched in between the dash and the dash support and was giving a very poor ground.  It isn't related to the problem I am now having though. 3- The copper ground straps from engine to body were in very poor shape- have been replaced and ground is now ok. 4- The battery ground cable only went to the engine and didn't have the little pigtail that grounds to the car.  It has been replaced with the proper type. 5- The old battery went bad in the car and would not take a charge- this was after I disconnected it and (stupidly) gave the old top post connector a love tap with a rubber mallet to help seat it on the battery and probably busted something in the battery. But the one remaining problem I have is one that I didn't have before.  All of the lights in the car pulse with the engine running.  They pulse between bright and dim at a rate of about 60-80 cycles per minute.   Driving down the road if I load up the alternator by switching on the high beams it made it stop pulsing, but only temporarily.  Sitting in the driveway it was pulsing and then when the powerglide is selected into drive- it would stop pulsing, but only temporarily.  Comes back within a few seconds.   With an analog meter between battery positive and ground the needle wags at the same rate but it is a small change in voltage- maybe .5 to 1 volt at most.  It isn't a drastic change between bright and dim but is very visable, especially at night.The car always cranks and starts strong so I don't suspect the cables or battery, the positive cable to starter is older but has a new terminal end.  Battery is new and seems fine.  I haven't been able to find any shorts or opens in the wiring.I suspect that the rectifier in the alternator is either going bad or that I damaged it when troubleshooting the voltage problem- I disconnected the battery cable with the engine running without even thinking about it, not supposed to do that.   Also, one thing that I had forgotten until writing this was that this whole issue started when I disconnected the old battery to use a wire feed welder on the car.  I disconnected the negative cable and not the positive cable - I may have fried the alternator or both alternator and voltage regulator?  Thought I would be ok by disconnecting just the negative cable.    I hate to spend money on an alternator and not have it fix the issue but it is my best guess at this point. Any ideas?Jim