6v generator voltages

[BearGap]

I have a '53 Jubilee with the original 6v positive ground system. The tractor runs fine. A while back I did snag some wires off the generator and pulled them loose, but that was repaired. However, I am not sure what I am seeing is typical. When the engine is off, the ammeter shows zero, and if lights are on it goes to 10amp discharge. When running I only show 5 amps charging, and 5 amps discharge if lights are on. Battery reads about 6.2 when off, about 6.3 when running. Field reads about 1.8 v and the armature reads about 7.5 v when running (all on a cheap DVM). Do these readings look normal or does this suggest I need a new regulator?

=Vic=

 

[old]

I have a '53 Jubilee with the original 6v positive ground system. The tractor runs fine. A while back I did snag some wires off the generator and pulled them loose, but that was repaired. However, I am not sure what I am seeing is typical. When the engine is off, the ammeter shows zero, and if lights are on it goes to 10amp discharge. When running I only show 5 amps charging, and 5 amps discharge if lights are on. Battery reads about 6.2 when off, about 6.3 when running. Field reads about 1.8 v and the armature reads about 7.5 v when running (all on a cheap DVM). Do these readings look normal or does this suggest I need a new regulator?

=Vic=

6.2 on the battery when not running is a bit on the low side

 

[Bern]

I have a '53 Jubilee with the original 6v positive ground system. The tractor runs fine. A while back I did snag some wires off the generator and pulled them loose, but that was repaired. However, I am not sure what I am seeing is typical. When the engine is off, the ammeter shows zero, and if lights are on it goes to 10amp discharge. When running I only show 5 amps charging, and 5 amps discharge if lights are on. Battery reads about 6.2 when off, about 6.3 when running. Field reads about 1.8 v and the armature reads about 7.5 v when running (all on a cheap DVM). Do these readings look normal or does this suggest I need a new regulator?

=Vic=

If you have 7.5 volts at the genny but only 6.3 at the battery, then you have excessive resistance between the two. This could either be in the wiring and/or the regulator. Voltage drop testing would help isolate the issue.

 

[sotxbill]

If you have 7.5 volts at the genny but only 6.3 at the battery, then you have excessive resistance between the two. This could either be in the wiring and/or the regulator. Voltage drop testing would help isolate the issue.

Betting of carboned up vr contacts??? or wire is damaged inside the insulation and only a few strands are left..Battery should slowly move up to 7.1 volts when running.. and should carry the lights with out a discharge.. but if testing at an idle , then the genny is NOT putting out till the engine is reved up... If its a genny, its got to be reved up to 1500,1600 to it to charge...

 

[Sean in PA]

6.2 on the battery when not running is a bit on the low side

And only 6.3 when it is running is even more on the low side.

 

[Bern]

Betting of carboned up vr contacts??? or wire is damaged inside the insulation and only a few strands are left..Battery should slowly move up to 7.1 volts when running.. and should carry the lights with out a discharge.. but if testing at an idle , then the genny is NOT putting out till the engine is reved up... If its a genny, its got to be reved up to 1500,1600 to it to charge...

Odds are it's the VR.

 

[BearGap]

Everything seemed OK and I even put a new battery in the Jubilee (the old one wouldn't hold a charge) and ordered a replacement regulator. The one I got looked identical to what was installed (6v + ground B-type) although there were marks on the cover where the screws hold it on, and I swapped them out. When starting up I immediately got over 15 amps of positive current flow and measured 7.1v on the battery, vs. 6.3v engine off. Left the tractor running to charge a bit while I put tools away, came back in less than 10 minutes and it was showing a nearly 5 amp discharge! Battery voltage is actually about 0.1v less when running than when off with the new regulator. So the replacement seems even worse than the old one since I only saw discharge if I ran lights before. Stopped and started several times and the new one certainly seems dead and while running I found no voltage at the field terminals. I did open the old one and use some contact cleaner on the relay contacts, and then reinstalled it back in the tractor. At least the old one once swapped back does show 1.8v periodically at the field.

So, I am contacting the seller for a refund or replacement. Anyone know of a good place to get a new regulator?

=Vic=

 

[Bern]

Everything seemed OK and I even put a new battery in the Jubilee (the old one wouldn't hold a charge) and ordered a replacement regulator. The one I got looked identical to what was installed (6v + ground B-type) although there were marks on the cover where the screws hold it on, and I swapped them out. When starting up I immediately got over 15 amps of positive current flow and measured 7.1v on the battery, vs. 6.3v engine off. Left the tractor running to charge a bit while I put tools away, came back in less than 10 minutes and it was showing a nearly 5 amp discharge! Battery voltage is actually about 0.1v less when running than when off with the new regulator. So the replacement seems even worse than the old one since I only saw discharge if I ran lights before. Stopped and started several times and the new one certainly seems dead and while running I found no voltage at the field terminals. I did open the old one and use some contact cleaner on the relay contacts, and then reinstalled it back in the tractor. At least the old one once swapped back does show 1.8v periodically at the field.

So, I am contacting the seller for a refund or replacement. Anyone know of a good place to get a new regulator?

=Vic=

Today's replacement parts made out of Chineseum certainly don't seem to last like the originals. I have found this to be especially true with voltage regulators. If you suspect that the one you took off is original, you might be better off trying to clean the contacts with a point file rather than continuing to replace them with ones of questionable quality.

 

[johnnmr]

I've had good luck with NOS American made regulators on ebay. Sometimes they
get kinda pricey tho. But they fit, function, and (seem to) last. Money well spent.

 

[ErnieD]

Everything seemed OK and I even put a new battery in the Jubilee (the old one wouldn't hold a charge) and ordered a replacement regulator. The one I got looked identical to what was installed (6v + ground B-type) although there were marks on the cover where the screws hold it on, and I swapped them out. When starting up I immediately got over 15 amps of positive current flow and measured 7.1v on the battery, vs. 6.3v engine off. Left the tractor running to charge a bit while I put tools away, came back in less than 10 minutes and it was showing a nearly 5 amp discharge! Battery voltage is actually about 0.1v less when running than when off with the new regulator. So the replacement seems even worse than the old one since I only saw discharge if I ran lights before. Stopped and started several times and the new one certainly seems dead and while running I found no voltage at the field terminals. I did open the old one and use some contact cleaner on the relay contacts, and then reinstalled it back in the tractor. At least the old one once swapped back does show 1.8v periodically at the field.

So, I am contacting the seller for a refund or replacement. Anyone know of a good place to get a new regulator?

=Vic=

Did you polarize the new voltage regulator?

 

[Jim.ME]

Did you polarize the new voltage regulator?

The generator is what gets polarized, not the regulator. The regulator is often mentioned as access to it is often easier than reaching a generator.

 

[Ozlander]

Now you know why both my NAA and my 860 now have alternators on them.
It's a lot easier to buy a good alternator then a good VR. And they last a whole lot longer.

 

[sotxbill]

Now you know why both my NAA and my 860 now have alternators on them.
It's a lot easier to buy a good alternator then a good VR. And they last a whole lot longer.

Sadly its come to that.. cheaper to just convert to 12 volt alternator and enjoy life more.

 

[BearGap]

Follow up, the tractor is back in service and charging correctly. I spent literally hours with the replacement regulator, and sometimes it would charge, but sometimes it was show negative amps. Tapping the cover would return it to positive amps, but the ammeter constantly swung wildly. In a final check I reinstalled the old regulator and checked everything (after cleaning up the contacts internally...just in case), but it still would not charge. The cutout relay was working as the field had voltage, and the generator was putting out 7.1v, but no charge to the battery. So I removed the cover of the regulator and while running the engine slowly bent the field coil spring attachment to increase tension. It was a delicate motion, and when I got to 6.8 volts I stopped and the battery is charging at about 10 amps now. When I run lights I still show positive charge. Perhaps I could have snuck up on 7 volts to the battery, but this is working and I am satisfied. I've also learned a lot about 6v generator/regulator systems.

=Vic=

 

[sotxbill]

great patch job, considering the most/some of the newer stuff is trash..