Voltage regulator

David68Newport

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I have a 68 newport 383. When car is idling it is charging around 15.5 volts. Run car around 2,000 rpms goes up to almost 18volts. Changed voltage regulator and new regulator kept volts in the mid 14's but after about 2 or 3 minutes of running regulator started to Smoke. Any help would be appreciated. Thanks.
 
I would check for a bad ground first. The base must have a good ground to the firewall and it should be grounded to the block. New electronics and switches are poorly made.
 
Would that cause it to Smoke? And the regulator was working keeping it around 14.5 volts. I put the old one back on back to 16 volts plus.
 
Would that cause it to Smoke? And the regulator was working keeping it around 14.5 volts. I put the old one back on back to 16 volts plus.
It probably smoked because it was a bad part. If the old one worked well, put it back on and call it a day. There have been so many members here, on B nad A Bodies lately with overcharging issues. Almost all were bad parts, bad grounds or wiring with bad connections and excessive resistance.
 
The old one is overcharging. I seen in another post guys using Regitar regulators off ebay. Maybe I'll give one of those a shot. The guy before me put a new alternator on it not sure the amp rating.
 
Seems like there is an ADJUSTMENT procedure described in the Chrysler factory service manual? Free download, as always, www.mymopar.com . IF the "original" regulator is the points type. If it is electronic, get a new one.

Chrysler used to sell an externally-adjustable voltage regulator, for situations where the vehicle saw only low speed, low duration use. An external screw could be adjusted for more charging level.

The brand of C-body, or even B-body, is not important as they all used the same regulator.

16V IS too much. Should be a good bit closer to 13.5V, IIRC.

CBODY67
 
I have seen many of the overseas voltage regulators smoke for the first few minutes of break in. The non-solid state type have an epoxy coating rear windings. This usually burns off in a few minutes. I was always nervous and monitored the voltage and current readings on the initial hookup if I used one. I got some of the solid state type from @FURYGT. They will give you better regulation and shouldn't smoke.
 
If its the "mechanical" type old school regulator..
Did the new regulator fail when it smoked? or does it still give you 14V? maybe it was simply burning off whatever residue on the current carrying conductors. if so the smoke will stop when the oil or whatever burns off. run it while watching the voltage, if the voltage maintains, there's nothing wrong with the regulator and it should stop smoking.
 
I will give it another try. It was regulating the voltage I just thought something was wrong with it smoking. I will give it another shot. Thanks for the input
 
The old one is overcharging. I seen in another post guys using Regitar regulators off ebay. Maybe I'll give one of those a shot. The guy before me put a new alternator on it not sure the amp rating.
Is the voltage regulator flatpack electronic? Pictured on Left. If so, it should not smoke
What brand?
Member @halifaxhops sells NOS voltage regulators that are high quality,
20250416_195119 ECU 1970 SF.jpg
 
I will give it another try. It was regulating the voltage I just thought something was wrong with it smoking. I will give it another shot. Thanks for the input


If you are trying to stay original then I would go the route of getting a NOS regulator as others suggested. My experience with external regulators hasn't been good. I eventually removed the external VR and replaced my alternator with a 1-wire GM alternator which is internally regulated. It works for me but my car is not for show or restoration, I drive it and want it to be reliable. After burning up several aftermarket external VRs, or seeing them output way to much voltage at their lowest setting I just couldn't trust the products I was buying.

Be safe and keep an extinguisher handy!
 
If you still have trouble, a dual field alternator (where both fields are isolated from housing ground) and a flat pack electronic voltage regulator like the one in post 10 require 1 additioinal wire to install. The alternator installs with the same brackets as your 1 wire alternator. The difference is that with the 2 isolated field wires, power input to the alternator is constant and the voltage regulator operates by varying ground to the alternator. This system puts much less stress on the voltage regulator than the box type voltage regulator in your picture which operates by turning current off and on to the alternator.
 
Thanks for the input guys I work weekends so I'll mess with this next week. I also have to address the fuel pump looked like it had fuel leaking from somewhere around the pump. Fuel leaking and electrical issues probably not the best combination
 
Put the new regulator back on smoked for a little then went away. Currently keeping voltage regulated will keep an eye on it thanks for the help
 
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