What's going on with my Generator?

[Nemo von Klepper]

This is my first time messing around with a generator, so essentially my first rodeo. The regulator is new from KW and the generator was just rebuilt, all 12v.
It doesn't seem to be charging:
Volt meter with the engine at about 1000rpms reads 12.2 and gradually sinks to 11.9. I was expecting somewhere around 14. I made sure the polarity was set, momentarily jumping the battery to the armature tab on the regulator (type A generator). I got a spark, a hum and the generator turned for a second the same direction as the engine. I considered this to be a good sign that the generator is in fact good. I noticed right before I turned the engine on that the amp meter which has been stubbornly been at zero was now marking at -50 amps. After I turned the engine on, the amp meter went back to just on the positive side of zero but I was only able to read 12v with the volt meter.

Next I took the lid off of the regulator. Everything there looks good, shiny and new.

I'm not sure what to do next.

[51 CJ3]

My generator experience is pretty limited and I don’t know at what engine RPM these generators need to produce power. I know on applications I am familiar with 1,000 rpm isn’t likely to get the generator generating. Usually 1200-1500 to get them started and they fall off line at 800-1000 but there are variables that can make up the difference. Most notable is the pulley sizes.

[Nemo von Klepper]

Ok, so the old timers are probably rolling their eyes about now, "Here we go with the 'My generator isn't charging' conversation again!"
Yup, you said it. A brief search over the internet yields many, many conversations on this subject, almost exactly like my conversation. So tomorrow I'll try it again at a much higher RPM. I expect it'll be fine, which will be a relief since I decided to rebuild the generator instead of an alternator at a likely higher cost. At least someone gave me the generator core. I want to get this rig on the road this summer so I'm chomping at the bit to move on to getting the brakes adjusted and start rolling.

[bmorgil]

We need LarrBeard to pipe in here but, I would be looking at the regulator. It might need adjustment.

[LarrBeard]

We need LarrBeard to pipe in here but, I would be looking at the regulator. It might need adjustment.

Herr von Klepper:

We “Old Guys” don’t mind answering the “Why isn’t my battery charging; what’s wrong with my generator?” questions. It makes us feel like we’re still important! Here is more than you probably want to know....

Disconnect the Field lead from the generator (at the generator case), that would generally be the smaller of the two terminals. Since you have a rebuilt – donated – generator, make sure you have Field and Armature figured out correctly.

You are going to ground the field terminal; by doing this you are going to bypass all of the relays and resistors in the voltage regulator and put the generator at close to full output. The most conservative way is to make up a test lamp (12-volt tail light bulb), hook one lead to a good frame ground and with the motor running, connect the other to the Field terminal. This allows a bunch of current to flow through the Field windings. The bulb should light up (it should be pretty bright) and you should get a + reading on the ammeter. This connects the light back to the battery through the Field windings and brushes, but limits the current through the Field coils to what the lamp would normally draw. (An 1141 bulb will draw about an amp or a little more – it might not bring the generator to full output, but it will give you an idea if things are alive).

The other less conservative way is to just take a clip lead and ground the Field terminal directly. This will put a LOT of current through the Field windings, so do not hold it too long or magic smoke will come out of somewhere, usually the insulation of the clip lead. This should put you at a hearty + reading on the ammeter – full output of the generator. Really old timers called this “full fielding” a generator.

This should give you an idea of your generator’s ability to turn RPM’s into amps. If you don’t get amps with these tests, I suspect an issue with the generator. If these checks give you amps, I’d replace the regulator. Defective (but new) voltage regulators are rare but not unheard of. Adjusting one is almost never necessary and it takes a lot more “stuff” that most of us want to fool with these days.

Good luck, let us know what you find – and we’ve not seen any pictures of the project lately.

[Nemo von Klepper]

Well, anymore anyone is an old timer if they learned to drive on a stick, type on a typewriter, dial a rotary phone, etc.

9334

I’ll take a look today when I need a break at work. Thanks for the input.

[Nemo von Klepper]

Well, tear it all! Yesterday afternoon when I went to try the jeep, the battery was completely flat with no obvious cause: headlights, blinkers, etc. It was too flat to even jump it by myself, so I've had it on the charger all night with the negative post disconnected.

Not sure what's going on now. Before I tried to re-polarize the gen the day before it was seemingly not charging, might be user error, but it also wasn't draining the battery. Not sure at this time if it's related, I might have just run the battery down too much when I was messing with it before.

Before I reconnect the battery, I'm going to check for an amp draw between the negative post and the cable. If that exists, I'll try to isolate the source: Check for continuity between the positive post on the battery and the field or armature posts on the gen, or voltage at the gen with the engine off. If those exist, then I'll check for continuity between the battery terminal and the field or armature terminals on the regulator.

My theory here is that one of the contacts on the regulator maybe stuck, creating an electro magnetic field in the gen., but then I don't know much about generators.

[Nemo von Klepper]

Ok, so now it might be charging, but my ammeter is going crazy. Related but separate issue so posting in a new thread.

[bmorgil]

Nemo it does sound like the regulator is having fits. Larry might jump in here with a circuit diagram. It sounds like the contacts in the cutout are having an issue.

Here is a good Voltage regulator 101.

http://www.secondchancegarage.com/public/83.cfm

[LarrBeard]

“OH, tear it all…”.. WOW – we’re not used to such refined phrases of frustration here. We’re more accustomed to SHYTE – or its’ equivalent.

You commented that the system was charging, but the ammeter was going crazy.

The link BMorgil gave you is a good description of what is happening in the regulator. Since the system is not showing a nigh current discharge when you shut off the Jeep, we can throw the “circuit breaker/reverse current relay” off the list of culprits, leaving us the over-voltage and over-current relays.

Now, on my truck, after a prolonged cranking period, the ammeter starts out at about a 30-amp charge, a steady value. After a bit, the ammeter does indeed go crazy. In my case it is because of the action of the over-voltage relay. After the cranking, the battery voltage is low, so the over-voltage relay sets the generator to full charge – the 30 or so amp reading. That is below the trip point of the over-current relay, so that relay stays out of the picture all of the time on my truck.

AS the battery starts to come up to a voltage that looks like it is charged, the over-voltage relay opens and connects a resistor in series with the field coil. That drops the charge current considerably – but since the battery isn’t really charged yet, its’ terminal voltage drops. That causes the over-voltage relay to close – removing the resistor from the field circuit and raises the charge rate again. Initially, the battery does not respond to the high charge current instantly – it takes a slug of energy (current over a period of time) to raise it up. The high charge rate raises the battery voltage and the cycle repeats until the battery really does come up to charge. During this period (on the truck maybe 10 or 15 seconds) the ammeter is going bonkers.

Once it does that, the battery’s charge is just being “tweaked” and it settles down to a constant low-rate (maybe 5 amp) charge rate. At this point the overvoltage relay is actually buzzing like a doorbell buzzer.. many times a second (One of these day I may look just to see how fast it is .. Hmmm).

You can take the cover off the regulator and feel the frames of the relay coils to see which one is going nutso on you – you can probably see it as well. Why is this happening? Troubleshooting by internet is risky … but:

A. If, for some reason the resistor that regulates field current via the over-voltage relay has opened, the regulator is in an ON-OFF mode, full charge or no charge. Simple answer – defective regulator – it ain’t worth trying to fix.
B. If your battery is deeply discharged, it could be getting into an interaction with both the over-current and over-voltage relay circuits.

We can way overthink these things and as a sparktrician and tinkerer I’ll piddle more with things like this that I should.

Make sure you have a good charge on the battery. If it tops off on the charger at 14-or so volts and still has issues in the Jeep, change the regulator.

Let us know what happens – and Happy Independence Day!

[Nemo von Klepper]

Hi thanks for the reply. So I got to run the jeep around the neighborhood a couple of times in the last few days. On a side note, it's fantastic to see people's eyes light up at the sight of what would have been a clunker 40 years ago, :D Even the teenagers seemed impressed.

So here are my impressions: The ammeter was wagging wildly until I engaged all of the electrics: headlights, blinkers, horn... Wow! that's it, no other accessories, lol. After the blinkers went on the meter went to a slight tick on the negative side. I turned the blinkers and electrics off and it would move smoothly in a small range around 0. I wasn't looking how it looked when I cranked the starter, but will do next time. I have a friend who is a major car collector coming out for something else on August. I'll have him look at it when he does.

There's a lot going on with this rig which hasn't seen the road in ages. Right now my biggest issue is a stall that seems to come from gas starvation. My first thought was bad ignition due to low voltage but it cranked over very strong. Still trying to figure the gas out. I red coated the tank a couple of years ago, so I don't think I have sediment in the tank but maybe there's a piece of coating flapping around the fuel line outtake. Might check the fuel pressure to make sure I'm not starving my carb. It also seems to be running rich. Heck, I'm a novice when it comes to all this stuff.

Another issue is that the front left brake is sticking. I suspect a retractor spring, maybe a stuck brake cylinder. Won't know for a while since KW's front hub pullers are on back order until Sept. Plenty of other stuff to keep me occupied in the mean time.

Pretty jazzed to have it finally running up and down the street, even with all of its bugs.

Happy Independence Day!

[51 CJ3]

Surely someone besides KW sells a hub puller that would work and has it in stock.

[bmorgil]

The KW hub puller is a re-production of the original Willys tool. It is a nice tool and well priced. You only need it if the front hub has stuck on. Most of the time the hub will come off with some "tapping" with a soft hammer. There are a few hub pullers that will work.

[Nemo von Klepper]

Ok, good to know on both accounts. I also bought the heavy duty hub puller as I was under the impression that they do separate jobs. I probably need to get into the e-brake at some point since it engages but seems to need a little adjusting, so that heavier puller will see some use soon. Thanks for pointing me in the right direction there too, BTW--it would have been quite a headache to try to put the lever on backwards from what it looked like in the shop diagrams and then frustrating to try to route the cable through the empty mount next to the exhaust, lol.
That's not to mention that doing the brakes again will probably happen sooner or later as I whittle down my priority list. After all this time I can officially say the jeep is in the driving debugging stage. I've wondered for the longest time if I would ever get there.

[bmorgil]

It is great being able to tool around in it a little bit. It lets you know it is a possibility! You definitely will have to keep the brakes high on the to do list.

To remove the Emergency brake drum, it comes off with the end yoke. Use a smaller two jaw puller hooked to the end yoke to pull the yoke and drum off together.

[Nemo von Klepper]

Thanks.

So this thread needs to be called, "What's Going on with my What Have You?".

This is probably not a big enough deal to warrant its own thread. I bought a grease gun from KW with a pile of other stuff. I can't seem to get any pressure out of it. It's a little different from my smaller grease gun or the one that my neighbor has. Does anyone have this model?
Anyway, unlike my smaller grease gun, I can't push the bottom cylinder in to force any air out. When you release the catch on the lower rod it just allows the spring on the cylinder to push the grease up to the pump, but I don't get any pressure if I pump. If I take the ball checks off, grease comes oozing out, so I don't think air pockets are my problem. If I had to guess, I'd say it was a bad o-ring on the pump piston or cup, but there are no user serviceable parts or way to disassemble the piston assembly. Any input is welcome. I still suspect user error even though I've done just about everything I can imagine to try to get pressure out of this thing.

[bmorgil]

On my grease guns there is a small plug at the pump end to purge the grease into the pump. Which pump do you have? Is it the reproduction hand pump? Give the boy's at KW a call, I know they will help you.

[Nemo von Klepper]

Is it the reproduction hand pump? Give the boy's at KW a call, I know they will help you.
Yup, I shot Mike an email. Just waiting for a reply. Looking at specs similars on the internet, it looks like it has a purge and a fill valve for filling from a bulk grease pump.

[TJones]

Nemo is the gun from KW’s you bought a cartridge type gun that you put a tube of grease in it?
If it is try unscrewing the tube the cartridge slides into about 2-3 turns and it will realease the air pocket on top of the grease and take it up to the pump handle, pump it a few times and screw the tube back in.
It may take a few try’s to get the pump primed before it starts pumping beings it’s brand new.

[gmwillys]

It never fails that when you work in a shop, all the grease guns are put up empty. Purging the air trapped in the head of the gun is a pain in the rear. TJones has the best advice that one can give for priming a new gun.

[TJones]

That’s exactly why I spent the money and bought a DEWALT 20V electric gun GM!!!
Plus I’m getting Lazy in my Golden Years:cool::D

[LarrBeard]

Naw - you're finally getting smart ...