So I've recently made a few threads in regard to 15.5 voltage at the battery being too high and many great members here have helped me get past ground issues, resistance, etc.
However, during all of this, I stumbled on a 70 alternator/regulator training film here:
At this point in the video, it mentions using the Miller C-4133 Voltage Regulator Tester. Here is a capture from the video:
Huh? I don't have to bolt each one on and run the regular tests? I was intrigued and found one on eBay -- the seller said guaranteed to work! So, a week later I got it today.
One of my questions going through my mind in my past voltage regulator issues is -- are the older voltage regulators set to a different value than the newer repros? So I hooked up my new purchase to a repro Mancini date code correct regulator (Black with White letters) and it tested at 14.2 volts. Hurray! I then hooked up a NOS AC Delco one I had from the 80s and it read 14.2. Great!
One of the questions I wondered was with higher amp alternators are the newer or older NOS regulators able to bring them down to 14.2 or do they register higher due to the higher amp alternators. Mine is a 95 AMP Powermaster and the NOS and Mancini repro could only get it to about 15.6-16 volts. So I found the adjustable Densco with help from other members and I got the voltage at the battery down to 14.2-14.5.
I then put in my NOS 37 amp alternator and the Mancini and NOS regulators were steady at 14.2 -- again, neither regulator was able to get the voltage down without the adjustable one with the 95 AMP Powermaster but they were fine with the 37 AMP alternator.
So then I tried the Densco adjustable regulator on the regulator tester and no matter where I turned the dial, it registered 16-17 volts -- even after turning the adjuster dial all the way down. Not sure about the tester on this one, but it does get the Powermaster in an acceptable range.
So, again, I am not an electronics wizard and I do not claim to understand why these do what they do, but I can follow directions.
I had two other NOS regulators in my bin and the tester read one as 9 volts and the other as 8 volts, so they went in the trash.
I wanted to share, because this was a really neat thing to try and it was very cool that it still works after all of these years. It does smell horribly like mildew, so it's living in a large ziplock until I need it again. Thought I'd share!
However, during all of this, I stumbled on a 70 alternator/regulator training film here:
At this point in the video, it mentions using the Miller C-4133 Voltage Regulator Tester. Here is a capture from the video:
Huh? I don't have to bolt each one on and run the regular tests? I was intrigued and found one on eBay -- the seller said guaranteed to work! So, a week later I got it today.
One of my questions going through my mind in my past voltage regulator issues is -- are the older voltage regulators set to a different value than the newer repros? So I hooked up my new purchase to a repro Mancini date code correct regulator (Black with White letters) and it tested at 14.2 volts. Hurray! I then hooked up a NOS AC Delco one I had from the 80s and it read 14.2. Great!
One of the questions I wondered was with higher amp alternators are the newer or older NOS regulators able to bring them down to 14.2 or do they register higher due to the higher amp alternators. Mine is a 95 AMP Powermaster and the NOS and Mancini repro could only get it to about 15.6-16 volts. So I found the adjustable Densco with help from other members and I got the voltage at the battery down to 14.2-14.5.
I then put in my NOS 37 amp alternator and the Mancini and NOS regulators were steady at 14.2 -- again, neither regulator was able to get the voltage down without the adjustable one with the 95 AMP Powermaster but they were fine with the 37 AMP alternator.
So then I tried the Densco adjustable regulator on the regulator tester and no matter where I turned the dial, it registered 16-17 volts -- even after turning the adjuster dial all the way down. Not sure about the tester on this one, but it does get the Powermaster in an acceptable range.
So, again, I am not an electronics wizard and I do not claim to understand why these do what they do, but I can follow directions.
I had two other NOS regulators in my bin and the tester read one as 9 volts and the other as 8 volts, so they went in the trash.I wanted to share, because this was a really neat thing to try and it was very cool that it still works after all of these years. It does smell horribly like mildew, so it's living in a large ziplock until I need it again. Thought I'd share!
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