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| The primary test instrument is the built in ammeter.
Generators put out according to speed. More power the faster its run. At idle most don't put out enough to keep up with ordinary lights and ignition. A larger pulley on a generator will slow it down and make the slow parade situation worse. Takes a smaller pulley on the generator to turn faster.
Its the one wire alternator that takes goosing to start charging, then it charges fine at low speed. The one I put on my gas 4020 takes about 1650 engine RPM to start charging then charges at idle. I put the smallest pulley on it that I could buy to spin it faster. Many an alternator even on a car turns twice as fast as the crankshaft so the small pulley on the tractor isn't hard on the alternator.
Using the ammeter, turn on the lights, the ammeter should show discharge. Crank the engine and with the engine running 30% above idle it should show charge.
The polarizing is to polarize the generator so it builds voltage in the same polarity as the battery. A generator can otherwise be satisfied with either polarity output based on the residual magnetism of the field poles. Polarizing MUST be done every time the generator has been tested in a shop, and if it sets a really long time should be done before starting the tractor. Polarizing is also called flashing because the usual technique is to short the B and A terminals on the cutout or the regulator and there will be a spark when that connection is broken after a few seconds which is all it takes to accomplish the polarization. A generator building with the wrong polarity can fry the cutout in the regulator.
Gerald J. | |
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Generator vs alternator
