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We have pretty well established there is no short in the battery lead wire or the ignition system. This clearly focuses our attention back to the regulator and the generator. Did you run the generator test I discussed above? You probably did not because it appears your standard wiring setup runs the ignition current through the regulator to the distributor and with a direct short you were fearful of burning out the regulator. We can bypass the regulator completely by combining the test method you just ran where you manually connected the battery wire to the negative pole on the coil and the generator test I discussed previously.
Remove the existing two wires on the generator - the armature and the field wires that go to the regulator. Now repolarize your generator by briefly touching the battery lead wire to the armature pole on the generator. You will observe a spark. Clip your negative lead on your volt meter to the armature pole and ground the positive lead to the tractor. Attach a separate jumper wire to the field pole on the generator and ground the other end of the jumper wire to the tractor. Connect the battery lead wire back on the negative pole of the coil and start the tractor at slow idle. While watching the volt meter, gradually increase engine RPM. You should observe the voltage increase on your volt meter as engine RPM increases. Run the engine RPM up to 10 or so volts. This is sufficient to test the generator output. Remember there is no regulation of the generator output with this test so do not run the engine at full throttle or for a sustained period of time with this test.
I made a new wire for the gen. pole and reg. I ran the tractor after polarizing and needle was just left of center. I gave it more gas and the needle flatlined again. I shut it off and the relay points stayed closed until I unhooked the battery. The wires are wired the same as the schematics. I will try this next.
Remove the generator. Either over haul it or have it tested.
Better yet. Convert to 12 volts. Would have been cheaper to begin with.
I have an excuse. CRS.
Well to start off with I see one major problem. No matter if the generator is working or not with a new battery you should have at least 6 volts at the Bat. terminal on the regulator. Verify voltage at Bat. terminal with engine off. If 6 volts or more then, but less then 6 while running, I would say there is a major short or wiring is wrong.
Try these links to see if they help.
Mark "birddog" Birdeau
Did you test the voltage output of both generators? The one with only 3 volts must have a partial short in it. I'm thinking the generator may still be good but it could be something as simple as a lead wire from a brush that is making contact inside with the generator housing. What seems to be happening is the generator is able to put out just enough current to close the cutout and once closed the higher voltage current in the battery rushes out to the shorted generator, registering the heavy discharge on your ammeter. Generators are not particularly hard to overhaul. II would remove the inspection cover and try to carefully examine the leads coming off the brush holders. As I recall one will be clearly grounded to the back end plate of the generator body but the other two should not be touching the generator body.
run a wire from + term (ground) of battery to FLD of regulator. If generator starts charging you either have another bad regulator, or regulator is not grounded. also use a small wire brush to clean connectors on generator, as well as making sure the case is getting a good ground. We fixed one at the MidMo fest that had enough tarnish on the brass nut and stud of the generator terminals that it was not making connection and would not charge.
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Just going off the top of my head, but I believe that a current reversal should open the cut-out points.
This whole thing has the sound of something miswired or lost grounds.
John, the way otherhalf describes his situation is that as soon as he starts the tractor and with the regulator wired into the system, the ammeter pegs to max discharge so it makes it hard to run the jumper test you recommend. The voltage numbers he provided do not make any sense either. In one of his posts, he even indicated that stopping the tractor did not cause the discharge to stop until he disconnected the battery cable, suggesting the discharge overloaded the cutout points and they got stuck shut. As to why the cutout is closing in the first place, I can only conclude that some generator output is doing it.
Jim, Typically, miswiring would be the first thing one would think of, but otherhalf says that the charging system was fine when he was working the tractor and then it suddenly started acting up. I do not think a lost ground should behave the the way he describes his problem. I do not know the answer to your question on the current reversal and relay closing/opening. As to what is closing the cutout in the first place, it should be the generator. What he seems to be experiencing with the cutout is the points may be burning slightly and sticking closed when the dead short occurs. Now, if the dead short could somehow energize the cutout coil in the first place and close the points, then it may not be the generator that is energizing the relay and closing the cutout but the battery. The latter seems unlikely to me.
Otherhalf has now tried two regulators, two generators and the same problem persists. Outside of checking the internals of the generator, as I suggested above, I am stumped at the moment.
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