Gererator generating question

[redmodelt]

I have a question about an Model a generator. As it is a 3 brush type might apply to T as well...
I have replaced the field coil, new brushes, new front bearing. The generator was flashed. I have put it on the tester. It motors clockwise. The 3 brush is set for 7 amps. I have check for shorts every way to Sunday. The armature check out on the growler. While it is on the test stand, if I pick up the 3ed brush, it's like taking a load off. With the 3ed brush down I have to really get the belt tight to make it charge. If the belt is loose I get nada and it acts like it is fighting, and acts like its trying to motor and generate at the same time. With the cutout mounted, it still has to have a good tight belt (when I get done I might need one too!) to start generating. any thoughts, or is this normal? Too add to this, the commutator was turned and the mica cut back, the brushes were fitted and line up nice with the segments.
Thanks

[Ted]

I can't tell you much without being there but if it has been polarized & it motors, I would think it should charge, providing the belt is tight. I don't remember the amount of belt deflection but it shouldn't be much.

[Tom Wesenberg]

"I have a question about an Model a generator. As it is a 3 brush type might apply to T as well...
I have replaced the field coil, new brushes, new front bearing. The generator was flashed."

Keep your clothes on......no need to flash the generator. LOL

As Ted said, it's so much easier to be there to check it out. The belt doesn't have to be tight to generate. I have about 1 1/2" easy push/pull midway from generator to water pump. 7 amps is too much charge unless you do a lot of very short drives. Is the cutout working correctly, so it cuts out when the generator stops?

I worked on an Autolite and a powerhouse both of which everything tested good, but the output was poor. They didn't charge at 1000 generator RPM, and they couldn't produce enough amps to carry the lights. The air gap was too much between the armature and field shoes. After I changed the armatures on each, for a better fit, they worked great.

[Ron in Quincy]

You mention the generator motors clockwise; its running in the wrong direction !!!, should motor counterclockwise on the bench test.

[redmodelt]

Ok first thing I will do is drop the amps down some. Note that the generator is not on the car. The cut out is working as it should. It is more the drag at lower RPM (belt slipping on test stand) that has me baffled.

[Tom Wesenberg]

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The generator should motor in the same direction it turns when mounted to the engine. When I have a generator on my test stand and motor it so it's turning the V belt and 1/3 H.P. electric motor, it draws about 10 amps.

[redmodelt]

Thanks, that sounds like the ball park I am in.