6v to 12v

You also need to swap the primary connections on the ignition coil and add a resistor on the 6 volt coil or change to a 12 volt coil. With negative ground the + primary terminal goes to the ignition switch and the - to the points, just opposite of positive ground.

As for the generator if it is modern enough to have a voltage regulator it won't put out 12 volts. If it is a 3 brush generator it might when turned fast enough. Might require a smaller generator pulley to spin fast enough for 12 volts at most tractor engine speeds.

A modern alternator definitely isn't original but has better regulation that most all generators and that makes for better battery life when the battery is fully charged but never overcharged. The three brush generator generally has the field hooked to part of the light switch so the operator sets the current, high after starting and low after hours of operation. Going too long on high gets rid of the water in the electrolyte, not going long enough on high fails to fully charge the battery. Otherwise for a generator it can take a 12 volt generator with regulator to charge reliably, but the alternator with internal regulator is a half century bettery design and very much better on the batteries.

And its absolutely necessary to flash the generator before starting but after connecting the negative ground battery to make it build voltage of the proper polarity.

A coin ground the field isn't enough to flash the generator but could help with another coil bridgeing the cap between the B and A terminals on the regulator.

Gerald J.

If you like the look of an alternator then that would be the easiest and most reliable way to go. If you like the look of a generator then take yours to a local starter-alternator -generator shop and they can usually rewire it for 12 volt. You will also a new voltage regulator.

Sometimes a 6 v generator will work with a 12 volt regulator, if the old gen is in good shape.  To "flash" a generator, you bypass the regulator.. So connect a wire to the "A" terminal of generator and touch the + battery terminal or "B" terminal of the regulator... What your thinking of with the quarter is touching the FIELD "F" terminal to ground, which does not polarize the generator, but bypasses a contact in the regulator and sometimes will make it "kick it" if stuck....... also a good way to test a generator and regulator.

If you have a distrubitor you need the diodes or it'll back feed power and not shut off. If you have a madneto you don't need them because magnetos are self generating and not connected to the power system.

I looked at the internal schematic of a CS 130 and the model with the "I" terminal has an internal resistor. I don't know if that resistor drops the voltage enough that you don't need a diode or not. You can give it a try without a diode and see what happens.

Edited by DougS - 11 Sep 2017 at 7:35pm