12 v regulator how to polarize

snead

Member
I am changing out my 12 volt regulator on my 74 ford 4400 tractor. I think its original . Do I need to polarize the regulator ?if yes how is it done. I'm also changing the entire wire harness that I got from AG tractors its supposed to be a complete replacement. the wire on this tractor has been messed with and needs to be replaced. Does anyone see any major problems doing this.
 
There is no polarizing of the regulator. It is the generator that is being polarized. The misconception arises from the fact that the polarizing operation is most often done at the regulator because the terminals are accessible/convenient. If nothing has been done to generator and battery has not been reversed +/-, the no polarization is necessary.
 
[ OK ,but if I remove the connections one at a time from the generator and the regulator to replace them with the NEW wire harness connectors , there would be a break in the circuit DO I THEN HAVE TO POLARIZE THE GENERATOR ? if yes how is it done.
 
The generator retains some residual magnetism. Unless it has been sitting around for a long time or wires were crossed during assembly there is no need to polarize it.
 
(quoted from post at 15:39:36 02/08/18) [ OK ,but if I remove the connections one at a time from the generator and the regulator to replace them with the NEW wire harness connectors , there would be a break in the circuit DO I THEN HAVE TO POLARIZE THE GENERATOR ? if yes how is it done.
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The generator is already disconnected from the battery.

The cutout relay in your regulator breaks the circuit from generator ARMature output to battery whenever the generator stops turning or whenever the generator output is less that the charge on the battery.
 
Does it have an alternator, 74 seems a little new for a generator, if alternator, then no polarizing needed.
 
(quoted from post at 22:47:22 02/09/18) Does it have an alternator, 74 seems a little new for a generator, if alternator, then no polarizing needed.

All 1965-1975 3 cylinder thousand series (2000/3000/4000) and the various Utility and Industrial models in those series (3400, 3500, 3550, 4400, 4500) all had 12 volt generators with external voltage regulators. I am pretty sure that the 5000, 5500 and 5550 all did as well. I believe the first Ford tractor to come from the factory with an alternator was the 7000, and then the next round, the x600 series and their contemporary Utility and Industrial models all had alternators.
 
That is my understanding as well. It puzzles me why it took Ford tractor so long to convert everything to alternators when the folks in the
automotive side of the house did so a full decade earlier.
 
(quoted from post at 10:49:59 02/10/18) That is my understanding as well. It puzzles me why it took Ford tractor so long to convert everything to alternators when the folks in the
automotive side of the house did so a full decade earlier.
..and then when they finally adapted them, why experiment with so many different brands?
 
They stuck with Motorola for quite a few years until they switched to Lucas, so I don't think I'd call that a big experiment. I suspect the
only reason they made the switch to Lucas was because so many of them were being made across the pond.
 

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