Adjustable voltage regulators

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moparlee

moparlee

64 Valiant
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Joplin, Mo
Has anybody played with them....I bought one and intend to play with it on my engine run stand. Just curious if anybody has messed with one as far as to see if they help us in anyway/worth messing with.
 
Meaning the old school mechanical ? Pre 1970 ?
The factory service manual goes into great detail on adjusting them.
 
There is absolutely no reason to have an adjustable VR. If the battery does not "run" at the correct voltage, fix the cause
No particular order:

1..Number ONE most likely is voltage drop in the harness---or ground--causing the battery to run high, even though the VR setpoint is correct
2...When checking, allow the battery to "normalize" and the engine to warm up--VR is temp sensitive
3...In some cases a bad battery---sulfated, EG
4...In a FEW cases the VR is actually bad--replace it
 
Not pre 70's stuff.

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67Dart273 said:
There is absolutely no reason to have an adjustable VR. If the battery does not "run" at the correct voltage, fix the cause
No particular order:

1..Number ONE most likely is voltage drop in the harness---or ground--causing the battery to run high, even though the VR setpoint is correct
2...When checking, allow the battery to "normalize" and the engine to warm up--VR is temp sensitive
3...In some cases a bad battery---sulfated, EG
4...In a FEW cases the VR is actually bad--replace it
Click to expand...
I think I've only ran into one voltage regulator that was truly bad. I say that and I played with the Mopar Performance constant 13.5 deal on my 64 Valiant....I don't know it's been 13 or 14 years ago now....and with hardly any use and it died.
 
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Darter6 said:
That's new to me. Never saw one. Thanks for the photos.
Click to expand...
I do think they sell one that looks pre 70 that is electronic but adjustable also. Heck they're selling some now that will bolt to the alternator and are adjustable also...eliminating the one on the firewall for those that want that....I have luck with Mopar stuff...so the one on the firewall is okey dokey to/for me.
 
I've forgotten, there is one or two aftermarket 70/ later that are adjustable. "In the day" you could buy a heavy duty truck one that was adjustable for the 69/ earlier grounded field ones. It was square, not rectangular like the older regulator. Standard/ Blue Streak made one.
 
67Dart273 said:
I've forgotten, there is one or two aftermarket 70/ later that are adjustable. "In the day" you could buy a heavy duty truck one that was adjustable for the 69/ earlier grounded field ones. It was square, not rectangular like the older regulator. Standard/ Blue Streak made one.
Click to expand...
I didn't realize that they even had that I guess....like this?

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^^That is exactly it^^ Those regulators were designed to handle heavier rotor current. I've not seen one on a car, typically pickups. I "guess" something like a police cruiser would have used them
 
I use the "transpro" ones and like them. I have had too many problems with the "part store" ones, not haveing the correct voltage output. I have seen as much as 2 volt variation between different regulators, on the same vehicle.
PS: I have them on my "early A's" with a 90 amp nippondenso alt.
 
A screwdriver isn’t the only thing that will adjust the voltage on an adjustable regulator like the ones above. Vibration, temperature, corrosion and age will cause the set point to change also. I imagine this is why you don’t see these but rarely.
 
The "IGN" terminal of a regulator is voltage setpoint. A regulator switches field on and off as necessary, to control average field current, resulting in voltage regulator. More field current, results in higher output voltage. Switching happens quickly, such that when reading with a meter, average voltage is present. Field inductance and battery filters to a fairly smooth voltage. Electronic regulators are much less noisy than mechanical.

A regulator is much like a thermostat for a heating system, you set thermostat for desired temperature. If room is cooler than setting, heater is switched "ON", if at or
above desired temperature, heater switched "OFF".

Feeding a battery is a bit more complicated, it is a chemical thing. Chemical activity increases with temperature. Regulators are designed to slightly increase setpoint voltage when cold, and decrease when hot. High end charging systems actually monitor battery temperature, but not found on early mopars. They assume under hood temperatures, same for regulator and battery.:).

Measuring "IGN" voltage, at 75F might read about 13.8V, with running engine, and be higher, 14.2V if cold. Reading battery will be slightly higher, due to voltage drops. Del has good post #4.
 
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