MTFCA Forum

Ok so here goes:

I rebuilt my generator.

I retrofitted an old cutout body to allow me to install the diode currently sold by Langs.

On the bench I set “null” on my generator with the third brush lifted.

With the generator in the car it was putting out too much and moving the third brush as far as it would go to lessen the output .. it was still putting out as much as 9 amps at 35-40 mph. At around 20 mph it’s in the 4 amp range.

This week my battery purchased in January died. It tested 6.2 ish volts but no cranking power. Had a load test done at the auto store. Dead.

So, my first question: did my generator over charging kill the battery?

Second question: should I loosen the four screws that hold the brush assembly on the generator and rotate the brush plate to allow setting the third brush to get me back to around 2 amps at 40 mph?

Setting the Model T Ford brush plate lead is very tricky
Follow this link and reset the brush plate lead using this procedure.
https://modeltfordfix.com/adjusting-the ... patterson/
Ron Patterson

Mark
Also be mindful of the admonitions in the last two paragraphs of this article.
Ron P

Your generator needs adjustment, but I think it's unlikely that your generator killed a battery that was new last January.

I am assuming you do not drive this car long distances with the lights off, and that you have a conventional battery of normal size, and that you start the car using the electric starter.

In most cases, turning on the lights, assuming you have original-type lighting, will load the generator such that it will not overcharge the battery under any circumstances.

My generator can deliver an indicated 10 amps at moderate road speeds. Turning on the lights drops the indicated charge rate to about zero. My car has standard lighting except for having 35 candlepower headlight bulbs instead of 21 candlepower bulbs. I'm using an older red top Optima 6 volt battery. I usually drive my car 15 to 50 miles every time I start it, and I've formed a habit of observing the amp meter and turning on the lights as needed to regulate the charge rate.

Reducing the maximum charge rate to about 5 to 6 amps is recommended for general use. Doing so will eliminate the need to manually regulate the charge rate by turning on the lights, but it may result in chronic undercharging of the battery if you drive a lot with the lights on.

The best solution is to buy an electronic generator regulator, if you can find one, or modify the generator to operate with a 1950's type electromechanical regulator.

Hey Pat, Before when my Fun Projects voltage regulator was still working I ran this car daily without the lights on. Since I have replaced that with a diode I have been turning on the lights for daytime driving when I am driving faster and see the ammeter in the 9 amp range.

That's way too high, if it will deliver 9 amps with the lights on.