- Home
- About Us
- Join/Renew
- Member Benefits
- Member Pages
- Log In
- Help
- Museum Store
I just had my generator rebuilt. Now it only generates when turned in the opposite direction that the engine turns it. Does anyone know how to reverse the wiring so that it will generate in the proper direction?
Your generator needs to be polarized, I believe, to reverse the polarity. There are discussions on the Internet about how to do so, but it depends on the system you have.
It’s not moving wires, it’s a momentary surge of current through the generator that makes it “push”” electricity the direction you wish….”
Chris,
The paragraph in Part-2 to scan starts with: A major failure-mechanism in generators….
Peter
Here is another one.
http://fergusontractors.org/fena/wp-content/uploads/Polarizing-a-Generator.pdf
Thank you all for your input. I’ve tried the techniques mentioned in the links to no avail. Probably because I am doing something wrong. I’ve got it in a generator shop and they don’t know what to do with it. I have forwarded the information in the suggested links and we’ll see what happens.
I’ll let you know what the shop does.
Rick
Rick,
What was the reason you had it rebuilt? Is the cutout/regulator ok?
Bill
F. J., All the above is good stuff, but the only fix is the flip wires to the two non adjustable brushes. If it charges fine when the rotation is backwards the shop has them backwards. If the only indicator you have is the amp meter in the dash, and not a volt meter at the generator then we need more info to diagnosis the problem. If the cutout works and the voltage is correct when rotation is wrong then go in and change the field wires. I have seen this before when shops are not told the rotation from the front of the generator. Karl
Bill,
The generator was rebuilt because it just stopped functioning. I never did get a good explanation other than the commutator was somehow involved. The cutout was my first thought but I am using a diode, and it tests just fine.
Karl,
The present shop says the voltage and amperage are just fine when the rotation is opposite that which the engine drives it at. Also, I used a volt meter on it when it was re-installed in the car and got no voltage, both before and after the diode. I have tested the circuit from where it connects to the diode using a battery charger and it operates normally.
Thanks to everyone.
Rick
Rick, reverse Field wires and all will be fine. Karl
Sounds like somebody was thinking negative ground… “Sparky” Karl to the rescue!
By the way, Karl, have you gotten any further on your experiment on rebuilding the water pumps through a local source?
Bob
Bravo Karl!
OK guys, its fixed. (Or so the shop says now.)
The shop found an intermittent short in the windings which was the cause of it not generating in the first place, and the field wires were reversed, which caused the reverse operation. So we were fighting two defects which made things a bit more difficult.
Thanks to everyone for the help, as it made it possible find the cause. All these modern electronics are making cars so difficult to repair. I almost think we should go back to gas lights and cranks!!
Thanks again to everyone.
Well done, Karl, you identified the major problem….and I retract my advice, listen to Karl! It’s wonderful to have the forum, and the Internet in general, to tap the vast knowledge that’s out there…I’ve seen obscure questions asked and answered many times…
Sounds like a difficult issue, the short and the incorrect wires sure would make most people pound their heads against the wall trying to figure it out. We recently had a set of windings made for a Pierce, the first five shops either would no longer do them due to “elderly employee who does them is sick/died”” or some other issue. We got them done on the seventh try after almost a 12 month delay. Its getting very difficult to get craftsmen to do some of these off the wall projects. I recently learned of an armature hand wound and the cost was almost two grand. Makes me want to have a spare generator for every car…..Ed”
I do have a spare generator. And starter. For each car. Rebuilt
I have a fellow 15 miles from me, he’s rebuilt starter and generators on my ’31 Pierce, our ’38 Packard Super Eight, and our ’27 Dodge cabriolet (the last of which has some oddball Northeast assemblies). Cost for each unit has been around $100, he does very nice work out of an itsy bitsy shop. As mentioned, one day it won’t be possible to find such talent.
I got the generator back and installed it over the weekend. It works!!!
I am really glad that I don’t have to rip it out again. I didn’t get to drive the car anywhere though as we had a storm run through the area.
Thanks to everyone for their help on this.