Adjusting mechanical voltage regulator?

[AR67GTX]

I’m replacing the solid state regulator in my 66 Satellite that was putting out 15 volts. The mechanical one purchase appears inside to be very similar to the Chrysler one in the service manual.

I first drove the car yesterday and upon starting the cold voltage was 13.6 volts followed by some smoke I guess from new components and oils (?). I warmed the car up and went on a short 5 mile drive. Upon returning voltage across the battery at idle was down to just over 12.6 - essentially just battery storage.

Before removing it I restarted it this morning and at slightly fast idle it was reading 13.3/13.4 volts. As the car idled and warmed up over about 10 minutes it dropped to 13.1 volts.

So, I removed it and opened it up and all looked OK inside - fusible wires fine, nothing scorched. Following the service manual I’ve lowered the spring retainer to slightly tension it more and raise the voltage level by some amount I’ll have to install It to determine. I think I need to get it up to about 14 volts cold.

I then measured the lower point gap and with the smallest wire gage I have (.010”) it snuggly went in. Factory setting for the Chrysler VR is .014”+/-.002”. So. . . My gap is a little small, but it’s also not a Chrysler VR. What is the significance of points gap? Does it by chance influence the voltage drop from cold to hot? Because it looks like my voltage drop is going to probably be .8 or .9 volts which seems a little great.

If not the point gap, what if anything, does influence the cold to hot voltage drop.

 

[pnora]

Heat changes the spring rate. Its been a long time but as I recall the FSM explained the adjustments. I would much rather have the newer style full electronic vs the old mechanical.

 

[twecomm]

Agree, the solid state regulator is preferable and much more reliable. 15 volts is indeed on the high side of acceptable. The available solid state voltage regulators, depending on where manufactured which is usually China, seem to have wide ranging results. There seems to be many threads on this topic. Keep in mind that the battery energy used to start will always deplete the battery especially if you need to crank a while to get fuel to the carb if cars been sitting for a few days, but after 15-20 minutes of driving I find that the battery once again should be close to full charge and battery volts as measured with engine running should be about a constant 13.6 volts at the battery. If you alternator gauge is still working as it should, you will see that it's taking a charge after starting and will center up once the battery is replenished. At least that's what I experience on my 66 Charger. I'm running a single field stock type alternator with a solid state regulator that looks like the original mechanical type. You said you saw signs of smoke from the regulator, that does not seem normal. Good luck with it.

 

[Pops1967GTX]

I'm still running a mechanical regulator . and points ignition.

 

[AR67GTX]

I was a little alarmed at the smoke at first but it tapered off after bi5 and the insides look fine. I suspect it was probably some sort of preservative on some of the parts smoking off. No smoke on starting it the second day. I have both a 66 and a 67 that both are running right at 15 volts with different SS regulators. I haven’t actually observed any issues from this but I don’t want to chance damaging the batteries. The things are getting too expensive to risk damaging.

Thanks Pop - I‘ll watch the video and see what I can learn.

 

[RJRENTON]

I'm still running a mechanical regulator . and points ignition.





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EXCELLENT presentation. When the upper contact is closed, it by-passes the parallel resistors (under the assembly), effectively putting full battery voltage on the alternator's rotating field. When the system voltage rises (after starting), the moving contact opens the upper point and "floats" between the upper contact and the lower contact. When in between the upper snd lower contacts, the current flows through the parallel resistors, reducing the alternator's field voltage and its output. During light electrical loads, the moving contact touches the lower stationary contact, which disconnects the alternator's rotating field. During normal operation, thr moving contact fluctuates between the upper stationary contact (full field voltage), the middle position, neither contact (reduced field voltage) and the lower stationary contact (zero field voltage) to maintain sn AVERAGE SYSTEM VOLTAGE of ~ 14,5 nominal volts. To adjust the voltage, the spring anchor is bent down slightly to INCREASE the system voltage; conversely to REDUCE the system voltage, the spring anchor is bent up slightly. The temperature compensation is accomplished thru the bi-metallic components of the moving contact assembly....not the spring. Just my opinion of course.....
BOB RENTON

 

[AR67GTX]

That video is a hoot. I think I had flashbacks to the 60s from it. Great stuff.

 

[AR67GTX]

FWIW - I found this on the web during a Google search. No idea if it’s fact or urban myth.


“The automatic in-built compensation ensures that when the ambient temperature is cold the alternator voltage is enhanced to compensate for the reduced chemical reaction time of the electrolyte by driving the charging at a higher voltage.Oct 7, 2015”

And this by Lucas, the prince of darkness:

“Temperature compensation​

The voltage characteristics of a lead-acid battery vary depending upon the ambient temperature, fluctuating by around 0.2 volts per 10°C rise or fall. Similarly the resistances of the copper windings in the regulator unit will also vary with temperature. The dynamo regulation circuits described so far will operate the same under all climatic conditions which means that the voltages supplied to charge the battery will be too high in summer and too low in winter.

The Lucas regulator units overcome this problem by using a temperature compensation device which makes its output conform more closely to the voltage characteristics of the battery. The device takes the form of a bi-metallic spring that is located behind the tensioning spring of the regulator contact armature. Being made from two different metals (each with different thermal expansion characteristics), the tension of the bi-metallic spring varies with temperature causing the charging voltages to be increased in the cold and reduced when it is hot.

Temperature compensation of the regulator output voltage is therefore automatically achieved to match the battery charging characteristics, without any input or adjustment by the rider.”

So, from this I conclude there isn’t any user adjustability for the amount of temp compensation.

 

[RJRENTON]

FWIW - I found this on the web during a Google search. No idea if it’s fact or urban myth.


“The automatic in-built compensation ensures that when the ambient temperature is cold the alternator voltage is enhanced to compensate for the reduced chemical reaction time of the electrolyte by driving the charging at a higher voltage.Oct 7, 2015”

And this by Lucas, the prince of darkness:

“Temperature compensation​

The voltage characteristics of a lead-acid battery vary depending upon the ambient temperature, fluctuating by around 0.2 volts per 10°C rise or fall. Similarly the resistances of the copper windings in the regulator unit will also vary with temperature. The dynamo regulation circuits described so far will operate the same under all climatic conditions which means that the voltages supplied to charge the battery will be too high in summer and too low in winter.

The Lucas regulator units overcome this problem by using a temperature compensation device which makes its output conform more closely to the voltage characteristics of the battery. The device takes the form of a bi-metallic spring that is located behind the tensioning spring of the regulator contact armature. Being made from two different metals (each with different thermal expansion characteristics), the tension of the bi-metallic spring varies with temperature causing the charging voltages to be increased in the cold and reduced when it is hot.

Temperature compensation of the regulator output voltage is therefore automatically achieved to match the battery charging characteristics, without any input or adjustment by the rider.”

So, from this I conclude there isn’t any user adjustability for the amount of temp compensation.

If it's the mechanical voltage regulator, ambient temperature compensation is accomplished thru the bi-metallic components of the moving contact assembly, to produce slightly higher alternator output voltage to provide higher charging voltage. If it's the electronic voltage regulator assembly, the ambient temperature compensation is accomplished thru the use of a thermistor (or temperature dependent resistor) as part of the internal voltage divider network that controls the main transistor's on/off time (in a current sinking spplication) that controls the alternator's field voltage and hence its output......just thought you might like to know.....
BOB RENTON

 

[pnora]

FWIW - I found this on the web during a Google search. No idea if it’s fact or urban myth.


“The automatic in-built compensation ensures that when the ambient temperature is cold the alternator voltage is enhanced to compensate for the reduced chemical reaction time of the electrolyte by driving the charging at a higher voltage.Oct 7, 2015”

And this by Lucas, the prince of darkness:

“Temperature compensation​

The voltage characteristics of a lead-acid battery vary depending upon the ambient temperature, fluctuating by around 0.2 volts per 10°C rise or fall. Similarly the resistances of the copper windings in the regulator unit will also vary with temperature. The dynamo regulation circuits described so far will operate the same under all climatic conditions which means that the voltages supplied to charge the battery will be too high in summer and too low in winter.

The Lucas regulator units overcome this problem by using a temperature compensation device which makes its output conform more closely to the voltage characteristics of the battery. The device takes the form of a bi-metallic spring that is located behind the tensioning spring of the regulator contact armature. Being made from two different metals (each with different thermal expansion characteristics), the tension of the bi-metallic spring varies with temperature causing the charging voltages to be increased in the cold and reduced when it is hot.

Temperature compensation of the regulator output voltage is therefore automatically achieved to match the battery charging characteristics, without any input or adjustment by the rider.”

So, from this I conclude there isn’t any user adjustability for the amount of temp compensation.

If you read the FSM it clearly states on adjustments just for what you are talking about. You adjust for summer and again for winter.

 

[AR67GTX]

Yes, I’ve read it. I know how to adjust voltage. I mentioned it in my first post. Just trying to determine if temperature voltage compensation is adjustable. RJRENTAN and I are concluding no - not at the user level.

 

[AR67GTX]

Success - after a few trial and error adjustments of spring tension I got 13.95 volts cold and 13.35 volts hot/warm. It doesn’t take much change on the spring tension to make a significant change in voltage. Should be good to keep my wet cell Interstate battery happy. Outside of lights, ignition, fan, vintage radio and clock I don’t have any other loads on the system. I decided to not mess with the point gap and the .6 volt compensation seems in the ballpark.

 

[RJRENTON]

Success - after a few trial and error adjustments of spring tension I got 13.95 volts cold and 13.35 volts hot/warm. It doesn’t take much change on the spring tension to make a significant change in voltage. Should be good to keep my wet cell Interstate battery happy. Outside of lights, ignition, fan, vintage radio and clock I don’t have any other loads on the system. I decided to not mess with the point gap and the .6 volt compensation seems in the ballpark.

Congratulations.....yes, the easiest and best way to adjust system voltage is the exact way you did...with the spring anchor point.....it's very simple but delicate....a little bit of change to tension will make a large system voltage change......
BOB RENTON

 

[AR67GTX]

Yes, it is a fine adjustment. The first try, when I fired the car, it jumped to about 16-1/2 volts and I hurriedly killed the motor. It took about 4 tries to wiggle it in to what I was shooting for.

 

[Sinitro]

Another solution is to install a Mopar adjustable voltage regulator, part#2444980 used in various Dodge & Plymouth 64-68...
EZ to tweak, just installed one on a friend's 65 Belvedere..

Just my $0.02...

 

[pnora]

Another solution is to install a Mopar adjustable voltage regulator, part#2444980 used in various Dodge & Plymouth 64-68...
EZ to tweak, just installed one on a friend's 65 Belvedere..

Just my $0.02...

View attachment 1568402

Back in the day there was two versions. One you adjust by bending the spring mount and the other was made by Essex and it had a screw adjustment.