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Here’s where I’m at with my generator/regulator/ammeter.

I believe the ammeter is fine. The bouncing around occurs when the current regulator relay and cutout relay operate.


Starting with fully charged battery at 6.35V. When I start the car (low idle), it drops to 6.28V. I can see the ammeter reading slightly negative and can make it go more negative by turning on lights etc… All as expected. When I increase to a fast idle, it does charge. The voltage goes up to close to 6.8V and the ammeter goes positive as it should. But, if I increase the idle more, as will happen when driving, the ammeter will suddenly bounce hard negative back to positive etc.. It will do this for a short while. I can hear a coil on the regulator operating. I assume that is the current regulator operating. That would make sense and I believe would result in a discharge state until the cutout coil opens. But, I don’t know if the extent of this chattering” is normal. Eventually, the ammeter just settles out to about zero and is very steady. I assume that is because the battery is fully charged at that point. Is this normal? Once in a while, it bounces hard enough negative that it pegs the ammeter and the ammeter sticks. A slight tap on it gets it going again. That’s understandable after 87 years. I need a nudge every now and then, too.

The only issue I have with the ammeter is that the scale is off center just a bit. Here is a picture with everything off. The needle is straight up, but the scale is off center. I’m sure that is an easy fix.

Some needle fluctuation is normal, but it should not bounce violently or come anywhere near pegging the needle.
Normally, after starting the engine and getting above idle speed, the ammeter will show a charge of 5 to 15 amps for a minute or two, then it will begin to move back toward zero if there is no heavy accessory load and the battery is in good condition.
Normally, the sounds from the regulator are too faint to hear

I think you have an intermittent short somewhere, or perhaps the regulator points are sticking. I'd look for a short in the wiring, the generator terminal posts, any of the battery cables, or any of the generator/regulator wiring. The engine needs a solid ground to the body and frame, and the regulator needs a solid ground to the generator. The generator could have an internal short in the armature or field windings, or in the brush holders.

Generally the regulator should operate around 200Hz. Wonder if the points are sticking for some reason, maybe burnt?

If you file them be sure to recalibrate the regulator.

Thanks, guys.

I did go through the wiring as much as I could. In particular, I confirmed that I had a good ground connection everywhere. I also gently “cleaned” the regulator points with 600 grit sandpaper.

It sounds like things are working as expected in broad terms. That is, charges for a few minutes, fluctuates a bit and then settles out about zero. But, that “fluctuates” part is clearly a bit much.

If I have an intermittent short somewhere, it seems like it must be internal to the generator. What started all of this was that the system had stopped charging at all. After some testing, everything pointed toward the generator. So, as mentioned in my earlier post, I pulled the generator out, took it apart and carefully cleaned everything. I didn’t see any obvious broken wires or nicks in insulation or wire coating, but that doesn’t mean there aren’t any.

When I get some time, I may pull the generator back out and take another look.

After cleaning points with sand paper whether voltage regulator or distributor, you should also burnish them with a clean piece of heavy paper. It removeds traces of grit and smooths the surfaces better than just paper alone.

I made a little progress today. I got the temperature gauge taken out and ready to send off for repair tomorrow. I also took out the oil pressure gauge since it wasn’t working and got a little good news. It turns out the tube was, in fact plugged. I think I had misunderstood Allen when he was working on the car. I thought he had said that he had completely disconnected the tube and found it to be clear. In fact, he said that he hadn’t gotten a chance to check to see if the tube was clear. Anyway, cleaned it up a bit while it was out and reinstalled. The original oil pressure gauge is now working great.

I also went for a short drive with a friend as I’m still investigating the generator. It seems to have settled down a bit, but still isn’t quite right. Anyway, the drive was fun with my little friend with me.

Making progress! Small victories are a good feeling.

I also pulled out the old worn out fire wall material. I’ll pull the toe board out soon and do some clean up on it and make a new floor board.

Before I boxed up the temperature gauge ai took a look at it and discovered the needle was stuck. I was able to free it up. So, that led me to testing it with a pot of water on the stove. Sure enough, the gauge was working, but not smoothly and only going to about 3/4 scale.

Chris Connors was a huge help! That’s who I was going to send it to for repair. He walked me through a the cleaning/lubrication process and how to calibrate it.

As a result, the gauge now operates very smoothly and I was able to get it calibrated pretty close. Straight up on the gauge is 180 degrees based on the scale in the car. I think I got it pretty good. It’s at least good enough that I invoked an old philosophy “better is the enemy of good enough”. Meaning, that if you get something where it needs to be, but continue to try and get it better or perfect, you may end up just making it work. I opted to stop while I was ahead.

It’s re-installed in the car and reading dead on where the new temporary gauge read. I’m pretty happy with that.

Please share the calibration and cleaning steps as I am pretty sure mine is off 30-40 degrees. Thanks!