VCCA Home Forums TECHNICAL - GENERAL Electrical - 6 volt generator high charge mode

I am having my 207 engine rebuilt. It is in a 35 standard coupe.
The engine rebuilder said that he sent the generator out to get rebuilt. He said that he was asked by the generator shop if that generator has a high charge mode. I am unfamiliar with this.
The car came with a heater. It does not have a radio.
Any info or thoughts appreciated.
Thanks
Dewane
CarDC

Hi Dewane,

That is a pretty good generator shop if they ask that question.

I do not know if the '35 cars had the "high charging" feature. Hopefully a '35 expert will jump in on this thread.

In 1936 there was a resistor wired into the circuit that supplied current to the field coils. This resistor was part of the circuit when the light switch was off. It reduced the current going to the field coils which reduced the output of the generator. When the light switch was pulled from the "Off" position this resistor was bypassed so more current went to the field coils. That provided a higher output. The light switch actually had a stop or position between off and when the parking lights and tail lights were on. The recommendation in the operators manual was to use that position to provide a higher charging rate to the battery especially in cold weather.

Remember that these were 3 brush generators. The output was at a fixed rate controlled by the position of the third brush and the amount of current in the field coils. These systems did not have a voltage regulator like the later Chevy's

Several ag tractors used that same system right up into the 1950's.
Very simple and very effective.

The standard equipment 1935 Standard generator whas three brushes and no voltage control. Amps adjusted by moving third brush and shoul be in the 10 to 12 amp range.
There was an optional higHer outPUT GENERATOR USED FOR CARSWITH RADIOS. iT HAD A ROUND VOLTAGE REGULATOR (VOLT. CONTROL) sittting on top of the generator...not to be confused with the little square cutout on top of the standard generator. VERY RARE.

I kind of wonder about the knowledge of the place and even wonder if they ar familar with a three brush generator and the adjustments required.

The resistor mentioned above was used on 1934-1936 Master cars and all 1937 cars.

So I would assume that what Gene said that my car should not have a high charging generator.
So is there a down side of using a high charging feature on a car without radio. I have a heater I was wondering if the heater fan created the need for the high charging output
Thanks
Dewane

The Heather Fan would not cause a use for high charging output.

I have a 1936 Standard and from what I have read, high output generators were used by commercial vehicles, taxis, construction vehicles ect. Otherwise standard output generators should work just fine.

Mind that you don't mix up the "higher output generator" Gene told you about with the "high charge light switch setting" Rusty told you about.
Two different things.

The three brush gen can "work," but is almost never really "right."
It's almost always going to be putting out too much (day) or not enough (night).
Yes, if you're careful you can reach a not too bad setting, but if you go for a long winter night drive you're going to lose charge.
All the over and under charging is bad for the battery.
It's not a big deal to change to a conventional generator and regulator.
A properly adjusted relay regulator is very effective.
I don't know if there are electronic substitutes, but it would not be a difficult circuit to design.
WL

It sounds like your car was stock so without knowing the background on your project and how it led to the engine rebuild and why the generator is being worked on, I would verify the model # of the generator that the shop has right now and make sure it is the correct one for the car based on the parts manual. I would question why the engine rebuilder wants it rebuilt besides being old and greasy and if/how they tested it? There is no point in them rebuilding an incorrect generator.

If it is the correct generator, make sure it is the correct shop to rebuild a generator of this age correctly as Gene alluded to above, as not many shops can do these properly. If it's the wrong generator source the proper one.

I spoke with the generator rebuilder and he said that the generator is correct. He asked about the light switch and the two positions.Thats is where my questions originated. He was quite familiar with that on the 35. I went and checked it and it is the two position switch which is correct for the car. He was concerned that the light switch was not correct as it may have been replaced at some time. He is going to rebuild it back to stock to the high charge as it was already.
Thank you everybody for the input. I have learned something new and continue to learn as I work on the car. I am doing a ground up restoration and an 80+ year old car that was just a car in its day. Thank goodness nothing has been modified on it. It was owned by a farmer and he did what he could to keep it going. Great thing is it was never driven in the winter!! It was put in a shed on the farm in 1976 and did not move until I bought it from his son in 2012. So I am having everything gone through so it does not leave me stranded when I finally finish it.

Dewane Frase
CarDC

From what the rebuilder is asking and telling you, it sounds to me like you are dealing with someone who definitely DOES know what they are talking about.
And they are definitely familiar with older charging systems.
If the quality of their work matches their apparent knowledge, you've lucked out!

I've run several units with that type of system and they actually work pretty well.
Especially the ones with a multi position light switch incorporating a "high charge/no lights" position.
They do require a little operator knowledge though... which you obviously now have.

Being a Standard it DOES NOT HAVE THE TWO POSITION SWITCH.

My 32’ Olds has the resistor on the light switch. Lights off, lower charge, lights on, higher charge. The generator is a three brush unit that also has a resistor on one brush.

The Chevrolet set-up allowed you yo pull out the light switch knob 1/2 notch to provide the higher charging rate. Automatically went to the higher rate when lights were switced on. Even sold a spacer so when the knob was pushed all the way in prvented from going all te way in and insured higher charge rate.

Gene which model had the light switch that could be adjusted to increase power voltage? i didnt see the original question just the answer. thanks Bob

The 1934-1936 Masters and all 1937 cars.