Ford CMP Voltage Regulators

[BCA]

Thanks for the comments, in particular to Tony for correcting the part number. My NOS positive ground voltage regulator has no markings or data plate to suggest the polarity - the only indication is from the packaging which gives the part number for positive ground model.
If you have an unmolested truck then the best indication of the original grounding would be from the holes sizes of the battery cable terminals.

Dodges: Both of my American 1/2-ton WC Dodges are missing the original battery cables so I follow the modern convention of using a negative ground: while the electrical systems charge OK, the ammeters read backwards indicating that they originally had positive grounding.
... Brian

[Ken Hughes]

Brian there is a way to change the polarity by holding down one of the contacts inside the regulator,i dont remember which one??,but you hold it down for an instant with motor running and it reverses the polarity,maybe some one can remember excactly?

[BCA]

I believe the polarization procedure has to do with the generator, rather than the voltage regulator.
... Brian

[Lynn Eades]

It is a matter of "polarising" the field magnets (they screw into the case and suport the field windings. This is done simply by hooking a wire from the live terminal of the battery and striking it to the field (small)terminal of the generator.
You ammeters in your Dodges can be fixed by simply swaping the wires on th back from one side to the other.
The "polarisation of the fields is important, because if its not done, the geny starts charging, the points(contacts) close, and when you stop the motor, they stay shut. the geny tries to "motor" but is held from doing so by the belt, and it cooks up your regulator and generator.