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I like driving my 1954 Cavalier to work soooooo.

I had noticed that now they turn off the sun before I drive home from work at night, that when I shut off the car at home the charge light was staying lit.

I'm of course driving with the headlights, radio, and front heater all on.

I examined the voltage regulator which looks like an aftermarket modern replacement, and the contacts on the cutout relay are so skimpy I would expect it only good for about 10 Amps.

When I was taking these things apart back in my youth (misspent) I recall very heavy contacts on the 6 volt cutout relay and usually two or three. I have a thorough understanding of how this all works.

The cutout contact had been heated to probably cherry red and was annealed to the point it was as soft as spaghetti.

I would expect all these 6 volt loads could easily be pulling as much as 40 Amps when all running.

I bought a new old stock regulator on eBay (waiting for arrival) that is rated at 6 Volt, 56 Amps, positive ground, indicated for Packard and others. I don't know if it is specific for (my car has Delco), or Autolite, or if it actually makes a difference. The regulator is not a brand I recognize but it is from the era.

I can't think positive or negative ground would change the operation of a Regulator.

Anyone here wish to comment on my plan here?

Jim

Jim,
Hopefully I can answer some of your questions. First off, if your regulator was only rated for say 10, 15 or 20 amps then it would restrict the generators output from exceeding that and therefore keep the cutout points from having to handle an excessive amount. Although single point cutout points are pretty common and they do in fact look as though they would not be able to handle the current sometimes. If your points have been overheated then you are right to replace it. Do you have any numbers off of your generator? With the numbers off your generator, I could figure out the correct regulator and regulator rating required. Feel free to call or email me direct with any other questions or don't hesitate to reply here for all others to read.
Jason
Advanced Electrical Rebuilders
www.aerrebuild.com
jason@aerrebuild.com

Thanks for the reply

With my Generator information, you could sell me a proper Regulator?

I will see if I can read the ID plate on the generator, I know it is Delco. The parts all seem to line up with what's in the service manual so I can look that up. The generator looks quite heavy duty compared with other 50's cars I played with. My car was with its original owner until it got collected in 1991 so I believe all the parts to be original (except this regulator).

The regulator that is still in the car looks like a modern replacement kind of thing and the cutout contact is well scorched and I presume it is welding its contacts. When I discovered the charge light on I lifted the hood and smacked the regulator and it dropped out. It has no numbers and says made in USA. I wondered how good the regulators that were sold by Kanter and such were.

As electronics is my business, I can't see how the contacts could handle much more than 15 Amps. The voltage is correct for 6 volt charging and I have no idea what the current limit would be for this regulator.

I had noticed the charge light glowing dimly occasionally for the last several months. The voltage drop across the contact is 1.5 volts, after I reworked the contact I got it down to 0.4 volts but still getting fairly hot.

I have driven the car about 3,000 miles since I got it last year, most of the time with the original radio on and sometimes the lights and heater fan.

The regulator I bought on eBay (which hasn't arrived yet) says 6 volt, Positive Ground, 42 to 56 Amps. It appears to have the same mounting configuration.

I don't know what would be different between a Delco and Autolite part as the theory of operation is the same.

I considered removing the cutout relay from the regulator and replacing it with a big 100 Amp diode hidden by the cover.

Jim

Jim,
Yes, I could provide you with the correct regulator if given all of your information. I'm sure the regulator you ordered will work just fine though. It will probably be a little higher amp than it should be , but I doubt it will give you any problems.

The Autolite and Delco's are for the most part (some exceptions)the same circuitry.

You could install a heavy diode in place of the cutout coil, but I would not recommend it. Keep in mind that a 100 amp diode only carries that rating when installed in a heat sink with air being blown over it to keep the temperature down, not stuck in an enclosed regulator case. A regulator base is far from an ideal heat sink. I usually only use diodes where the generators output is 20 amps or under. I think the problem you are experiencing is unique, usually the problem with mechanical regulators is in the field control coil(s).

Let me know if I can help you in any way.

When a diode goes bad does it create an open circuit or a closed circuit????

I would be interested in pursuing the original part (I like originality); I should make contact off line?

I am going to check the brushes in the generator sometime soon, are they hard to come by?

According to the service manual the Generator is Delco-Remy 1102778.

The Regulator is (should be) 1118829.

All rated at 45 Amps (6 Volt).

I didn't actually crawl under the hood but so far the part numbers have all matched the service manual numbers perfectly. The electrical is all Delco-Remy stuff.

No possible way the existing regulator could carry 45 Amps through the little single contact even though the voltage stayed up with all the accessories running.

The original regulators employed some temperature compensation which boosted the charge rate in cold weather which I know this replijunk regulator doesn't provide.

I have the eBay item coming so I will know how this all works out soon.

I have a pile of stud mount diodes that are rated at 150 Amps with a 600 volt peak reverse. I have both the anode to stud and cathode to stud version. I figured I could remove the old cutout relay and put the best diode in its place and mount it so I get some heat sink value through the base of the regulator. The Armature voltage comes to the cutout through the relay frame and goes out to the battery terminal through the contact so mechanically this should be easy to adapt and still put the cover back on. This would preserve the voltage and current relays. I don't know if the current relay can get the generator up to 45 Amps but the contacts look OK. I would expect the diode to have about 0.7 volts saturation drop.

Here in Phoenix AZ it can easily get up to 120 degrees F ambient outside, and under the hood it will be considerably hotter than that. These diodes can run at 392 degrees F so they may survive.

Diodes usually fail shorted which should not cause more trouble than a dead battery.

Jim

Jim,
So, you want an original Delco regulator? Does it have to be the correct number or would a later part number be ok?

As for the diode, your choice obviously. I just know I've seen 70 amp diodes fail with only 15 amps going through it. If it fails shorted, you could have more than just a dead battery. That will energize your generator and it will try and motor as long as there is current going to it, you could damage the armature as well. It would be best if it failed open.

I have brushes, they are still readily available.

Unfortunately, the quality of these and all replacement aftermarket regulators has gone down in the last few years. I've had problems with the USA and import replacements, sometimes right out of the box. Society demand for faster and cheaper goods has really taken a hit on quality, I'm sure your familiar with this.

Again thanks for the comments.

I sent Jason a direct email.

I like the parts to look like they did when the car was new and I am aware the quality was a good bit better back-in-the-day.

I am going to try my eBay after market regulator but I want to pursue an original part. I'm only in the eBay part $30 and it is new old stock.

I probably won't try the diode trick, I do agree that it could damage the armature and in my experience diodes always fail shorted. I don't want any solid state devices in my vacuum tube era car.

Jim