[rotorwrench]

Since they are not a motor, they will have low torque and rpm compared to a normal electric motor design of the same size.

I don't motor them to polarize the fields. The fields are connected to the 3rd brush and ground so I isolate the 3rd brush by disconnecting the lead and jumper it to the negative post on the battery. I then jumper the positive post of the battery to the case ground of the generator momentarily. This puts a good magnetic gauss into the field pole shoes with proper polarity for positive ground. If polarizing through the armature, It doesn't get as good a magnetic gauss level as with direct field coil magnetization.

A fellow I used to work for would attach a test light to the output terminal and the other to the case and spin it up with a wire brush wheel on a grinder motor. A better way would be to attach an ammeter in the power line and see what kind of amperage will come out of it but the test light will tell if it will generate or not. Put the cut out on and install if it generates current and then use the amp meter in the output line to adjust the 3rd brush in the car.