Generator

[Shortdog]

What voltage should a generator on a 31 put out at idle and about 1500 RPM's?
Thanks Johnny

[Mike V. Florida]

If your battery reads 6.3 volts with the engine off, then it should read about 6.7 with the generator charging.

[Tom Wesenberg]

At 500 engine RPM a good generator should start to put out a hair more than battery voltage. Unless you install an electronic voltage regulator the voltage will be set by the battery, and adjusting the third brush will change the amps being pumped into the battery.

500 engine RPM gives the generator 750 RPM.

[Kurt in NJ]

If it is not hooked to a battery it can make over 40 volts for a short time----then it makes very low volts

[Shortdog]

Thanks everyone for the info. The battery was 5.8 and when I started the motor the generator was putting out 6.10. I was working on my turn signal's and that was why the battery was low.

[Tom Wesenberg]

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Originally Posted by Shortdog

Thanks everyone for the info. The battery was 5.8 and when I started the motor the generator was putting out 6.10. I was working on my turn signal's and that was why the battery was low.

I only use an analog meter for Model A checks. 5.8 would indicate a dead battery for all practical purposes. Is you meter correct and calibrated?

At least you do indicate the generator is charging.

[Shortdog]

Originally Posted by Tom Wesenberg

I only use an analog meter for Model A checks. 5.8 would indicate a dead battery for all practical purposes. Is you meter correct and calibrated?

At least you do indicate the generator is charging.

I don't have an analog meter. Need to get one. My meter has never been calibrated but it is a good one. On the other hand I have only used it on a 12 vote system that has a alternator.

[Shortdog]

Originally Posted by Tom Wesenberg

At 500 engine RPM a good generator should start to put out a hair more than battery voltage. Unless you install an electronic voltage regulator the voltage will be set by the battery, and adjusting the third brush will change the amps being pumped into the battery.

500 engine RPM gives the generator 750 RPM.

Tom
You said adjusting the third brush. What is the third Brush? Also do you have an electronic voltage regulator on yours?

[Mike V. Florida]

Here is a selected picture on the wiring diagram showing the generator. The third brush is movable to allow for different output.

To increase the output, you move the adjustable brush down.

[walt jones]

The third brush is located under the cover ring at the rear of the generator. The cover ring must be removed to see and adjust the third brush.

[Tom Wesenberg]

Originally Posted by Shortdog

Tom
You said adjusting the third brush. What is the third Brush? Also do you have an electronic voltage regulator on yours?

Yes, I always use a regulator, as it's so much better for the battery and bulbs.

Since few people actually move the adjustable brush, it may be stuck and require much effort to make it move. With the engine off try to move it by prying against the post, not the brush. Using the case opening as a fulcrum, and using a long screwdriver, you should be able to move it up or down.

The thinnest brush, between the output and ground brush, is the adjustable brush.

[Pilotdave]

Appears that the adjustable brush moves clockwise (in your photo) along the approx 90 degree arc between the output and ground brushes....yes?

[Tom Wesenberg]

Originally Posted by Pilotdave

Appears that the adjustable brush moves clockwise (in your photo) along the approx 90 degree arc between the output and ground brushes....yes?

Moving the brush clockwise in my picture would be downward on the car. This moves it closer to the output brush, which means it sends more voltage to the field windings, which raises the output current (amps).

[Pilotdave]

Thanks, Tom. Very helpful to have the words along with the picture.

[Marshall V. Daut]

It's easier to remember that to move the charging rate UP, move the 3rd brush holder DOWN, as you are looking into the mounted generator. To move the charging rate DOWN, move the brush holder UP. In other words, do the opposite of what you want the generator to do.
Marshall

[Shortdog]

Tom,
Is this like the Regulator that you have.


Model A Ford Generator Cut Out - Electronic Voltage Regulator Version - Ford Script - 6 Volt Positive Ground Only

http://htsmall.macsautoparts.com/ass...u/64-20675.jpg

[Tom Wesenberg]

Originally Posted by Shortdog

Tom,
Is this like the Regulator that you have.


Model A Ford Generator Cut Out - Electronic Voltage Regulator Version - Ford Script - 6 Volt Positive Ground Only

http://htsmall.macsautoparts.com/ass...u/64-20675.jpg

No, mine looks like this one.

[Kevin in NJ]

As pointed out, the generator is really a current producing device. A voltage measured is a reflection of the resistance in the circuit (will battery).

The battery is the 'voltage regulator' for a factory Model A. A change in the resistance of the cells or in the connections to the battery will affect the voltage you measure.

Putting in Tom's regulator will control the voltage and the current and take some thinking out of operating the A's charging system. I would recommend that if you do not have a good understanding of electricity.

[Shortdog]

Thanks everyone for the info. if a person doesn't ask he doesn't get a answer. I don't mind asking. I have the red book coming. Has anyone thought about changing to a alternator.
Johnny

[CarlG]

Originally Posted by Shortdog

... Has anyone thought about changing to a alternator.
Johnny

...

[30ccpickup]

This is wide open for opinion. I have two Model A's one with a generator and one with an altinator both are in good working order and preform well. I prefer the generator only because when I open the hood it looks correct, but how the alternator looks does not bother me enough to spend the money to replace it on the other A. In the end each to their own.

And worms are good... Makes for a longer thread

[Shortdog]

Originally Posted by 2rosella

I have one of Toms Electronic Voltage Regulator (EVR) on my 6v 5 brush generator and it's absolutely fantastic. Takes all the guesswork out of manually adjusting the 3rd brush.

I am new to this site. Tell me, Which Tom are you talking about. I don't want to go to an alternator, but I need a little more hump for my turn signals. The people here in Louisiana don't know arm signals. I put the turn signals on and they are not connected to the other lights. My old hunk of junk is just about as original as you will find and I want to keep it that way. I don't drive it every day, but I do drive it. Runs great. Thanks Johnny

[Patrick L.]

Tom is Tom Wesenberg. His EVR is easy to install, its hidden in the generator and its bulletproof.

I don't blame you for not wanting an alternator.

[Willie Krash]

Tom is a gentleman and doesn't plug his stuff....So how much does that VR cost?
OTOH, it might be a love of labor.

[J Franklin]

Hi Tom, would your regulator work in a model T generator?

[Tom Wesenberg]

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Originally Posted by J Franklin

Hi Tom, would your regulator work in a model T generator?

Model T's are negative ground, and my EVR's are only for + ground.

[old31]

Tom, what is the difference in operation between your EVR and:

http://www.snydersantiqueauto.com/se...r-cut-out-4290

[tbirdtbird]

"The people here in Louisiana don't know arm signals"

actually, no one does anymore

[Tom Wesenberg]

Originally Posted by old31

Tom, what is the difference in operation between your EVR and:

http://www.snydersantiqueauto.com/se...r-cut-out-4290

The one from Snyder's controls the voltage after it leaves the generator. The one I make controls the voltage by regulating the strength of the magnetic field by controlling the voltage going into the field windings. Both work to regulate voltage, just in different ways.

For longer battery life and safer output to prevent blown bulbs, I wouldn't be without a voltage regulator.

[eagle]

I have the voltage regulator in a cutout can. It works very well. You will want to adjust the third brush for the maximum current you want the generator to output before you install it. Maybe 12 amps or so, then Install the regulator. Don't use the car ammeter unless you have tested it and know it's accurate. Use a modern good quality ammeter, then you KNOW what is happenning. I guess if I was doing it over again I would take a look at Tom's regulator. One disadvantage of updating to a voltage regulator is you now have some somewhat sensitive electronics on your A. You will ruin it if you aren't somewhat careful. I one time saw a guy jumping someone ele's car with his. First thing he did was connect the jumper cables to the running car, then arc them together to "test" the connection, then proceed to try to connect the cables backward on the dead car, it's a wonder either car lived through it! (See my signature line!)

[tbirdtbird]

"First thing he did was connect the jumper cables to the running car, then arc them together to "test" the connection"

Yikes, time to forfeit the tools....

[eagle]

Originally Posted by tbirdtbird

"First thing he did was connect the jumper cables to the running car, then arc them together to "test" the connection"

Yikes, time to forfeit the tools....

Yeah, it was a modern car so its amazing the electronics of both cars lived through it.