Charging rate

blgitn

Senior Member
Happy Easter!!

I added an amp to my charge rate today, because it was easier than mounting 6.50-20's.
At a brisk idle it charges just under 10.
With the high beams on it's right at zero.
Over half-throttle the charge rate drops off; is this normal?

I tightened the belt and cleaned the commutator--no difference.

R/ Roger.
 
It sounds normal, but I wouldn't run a 10 amp charge or you will be adding a lot of water to the battery and shorten it's life.

If I didn't use my EVR then I'd set my charge to about 2 amps.
 
a lot of Aers don't use their cars at night.
As Tom says with car running daytime (electrical load is ignition) 2 is super.

If you run at night and need headlites, we at that time move the brush to get more amps and then move the brush back at the end of the run. 10 all the time will spell trouble as he says
 
Can someone add a little more explanation to this? Are you talking about a system with an alternator? How do you adjust the output as you've described?

Thanks!
 
No not an alternator, the generators in the model A use a 3 brush system, two are fixed and the third can be shifted to change the generator output. Drive at night a lot, raise the charge rate, don't drive at night, lower it.

But yes, I agree , 10 is too much
 
I bought the voltage regulator from Macs that looks like an original cutout. No need to adjust the 3rd brush any more. Night or day. Charges the battery at maybe 6-8 amps for a few minutes when first started, then makes its way down to just blipping the needle. (blipping is a technical term...)
 
Eagle:
What's the process; set the third-brush-charge rate up high and then install the 'regulated cut-out'?

Tom:
So it's OK for the charge rate to drop off above a certain RPM? This is an AA, so the rate begins to drop off before I hit 40 mph.

R/ Roger.
 
Adjust the generator 3rd leg output to the max you feel comfortable with, I set mine at 16 amps, then install the regulator. Done, no more mess'n around with a flashlight after dark trying to adjust the output. Tom W makes an internal regulator you can install into the generator as well.
 
Eagle:
What's the process; set the third-brush-charge rate up high and then install the 'regulated cut-out'?

Tom:
So it's OK for the charge rate to drop off above a certain RPM? This is an AA, so the rate begins to drop off before I hit 40 mph.

R/ Roger.

40 MPH in a double A is fairly high engine RPM. A generator has a point of maximum output, and at higher RPM the output will fall off slightly, but it shouldn't be much. You might have weak brush springs or a poor commutator if you notice the output falling off. I've also seen poor connections, such as where the field windings wire is twisted and soldered to join the two fields. I've seen a couple with no solder, or a loose solder joint.
 
Eagle:
What's the process; set the third-brush-charge rate up high and then install the 'regulated cut-out'?

Tom:
So it's OK for the charge rate to drop off above a certain RPM? This is an AA, so the rate begins to drop off before I hit 40 mph.

R/ Roger.




Tom will probably answer this also. I'm not him, but, no, the rate should not fall like that. The brushes may be bouncing due to the commutator being out of round or the springs may be getting weak. A 'AA' can go 40mph ?
 
The amp output on my generator is very low - about 1 amp. Moving the 3rd brush doesn't seem to have any effect. Is this because I might have an aftermarket voltage regulator built inside the cutout? Can I run a jumper around the cutout to see if the amperage increases?

If I turn on lights with the motor stopped the amp meter reads heavy negative so I think the amp meter is fairly accurate.
 
The amp output on my generator is very low - about 1 amp. Moving the 3rd brush doesn't seem to have any effect. Is this because I might have an aftermarket voltage regulator built inside the cutout? Can I run a jumper around the cutout to see if the amperage increases?

If I turn on lights with the motor stopped the amp meter reads heavy negative so I think the amp meter is fairly accurate.

What headlamps do you have? Sealed beam and some halogen draw more amps than the stock generator can put out. What does your ammeter show with the lights on and you go from idle to higher RPM? If the ammeter moves to the charge side, or upscale, then you must have a voltage regulator. If you have John Regan's in the cutout, then you NEVER want to jump the two cutout terminals, as John said that it will burn out the unit. If you have my EVR, which is installed inside hte generator and replaces the adjustable brush, then you can jump across the 2 cutout terminals because it would be a stock cutout or a diode cutout.

Don't guess at which EVR you have. You might have to remove the band and see if the adjustable brush is in place, or an EVR is in it's place.

BTW, with a good generator and an EVR, my ammeter doesn't go negative when I have the lights on and the engine is at idle.
 
Tom,

I am running standard light bulbs (6V). I do not have the internal EVR as the 3rd brush is installed. I do not know if I have a regulator inside the cutout.

I just started the car and when I go from idle to high speed the amp meter moves up to +1-2 amps. returning to idle the needle drops to zero.

With the headlights on at high speed the amp meter runs at -8 amps.

I have measure the voltage in the past and it will go from about 6.4 volts (not running) to about 7.1 volts running. Should I try an eliminate the cut out from the circut all together just to test the generator ?
 
Yes, just remove the cutout and either install another cutout, or just jump the wires to the generator post. Just don't leave them connected for more than a minute unless the car is running, and don't run the generator without the battery connected to it.

So, you could just jumper to the post, then start the engine right away and check the ammeter at idle and higher RPM. Check it with the lights off, and then on.
 
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