Generator wiring

[OUTFXD]

Jacquilines Generator stopped charging.

 

The amp meter just sits in discharge mode (It twitches when you turn the ignition on and off) and she failed the "Will it continue to run with the ground pulled" test.

 

As I said before, the entire car was rewired with radio-shack quality wire in four colors.

 

The wires going between the Generator and the Voltage regulator,  while being different colors, are unmarked and I see no markings on the generator. The wires are also equal length with crimp on connectors and entirely sepparate from the wire loom. No clue if they are even the correct colors.

 

My generator has two wire connections. One on the side about mid point. The other on the side almost all the way to the back.  Which one should be connected to ARM and which to FLD on the voltage regulator?

 

Thanks for putting up with me!

Edited February 1, 2022 by OUTFXD

[kencombs]

Normally the ARM wire is much larger than the FLD.   The studs they bolt to are also different sizes.  Without a pic, I can't be sure but the rear one is probably the ARM.  It may need to be polarized.

[FarmerJon]

Here are the two reference pictures I took when I had my generator out, I will take a picture from a service manual when I get home, if someone hasn't beat me to it. 

Right or wrong, I flash my generator by shorting between the bottom two connectors on my voltage regulator. 

I think they are Batt. And Field?

I just stick a screwdriver down there and cross them till I see a spark or two. 

Probably a better, more scientific way, but...my car charges.

 

Also to note, I don't believe generators charge much at all at idle. At least mine doesn't. 

[Bryan]

Here's my pics. Larger wire from Gen went to top of regulator.

[OUTFXD]

Ok so looks like the BIG wire is ARM and goes to the TOP of the Regulator.

 

The little wire is the FLD and goes to the middle.

 

and the bottom connection to the regulator is Keyed ignition.

[OUTFXD]

I learned to check the charging system by pulling the ground off the battery while the engine is running.  if the engine stays running, Congrats your charging system works.

 

I realized this was on a 12v system with an alternator and may not apply to a 6v system with a Generator.

 

Does this trick work on 6v systems?

[greg g]

You test the generator  by temporarily grounding the field terminal.the smaller one on the gen.  Start the car, if you have a hand throttle adjust it to 1000 to 1200 rpm.  If no throttle, use the idle speed screw to increase the idle.  This energizes the field coil bypassing the regulator.  If the Amp gauge pegs to positive charge, the generator  is OK and the fault is in the regulator or wires between the regulator and generator.  If the reg is at fault it may be fixed by dressing the three points sets within.  If the generator  is faulty it in most cases will be from needing new brushes, or at least checking them for wear and how their connections are.

[OUTFXD]

Three Multipul Digit readers later (I guess that why they are Multipul),  I got one that works. Disconnected the wires from the generator.  Jumped the Fld to the ARM,  Started the car, and ran 1 lead to ground, the other to the ARM terminal and got 4.3 volts.

 

Now Im not good with Electricals.  But that seems kinda weak.

[Sam Buchanan]

After you get tired of messing around with the generator, regulator, etc, replace the whole conglomeration with a one-wire alternator and drive happily ever after with a fully charged battery.    ?

Edited February 2, 2022 by Sam Buchanan

[OUTFXD]

3 hours ago, Sam Buchanan said:

After you get tired of messing around with the generator, regulator, etc, replace the whole conglomeration with a one-wire alternator and drive happily ever after with a fully charged battery.    ?

a full 12v conversion complete with rewiring, modern Fuse box, Electric fan, Electronic Ignition, and LED bulbs is underway.  However this is quite costly. Repairing the existing equipment is not AS costly,  but still not cheap and would push back the planned upgrades due to lost financials. That and I am hesitant to replace something that is going to have to be changed out soon anyways.

 

This puts me in quite the rough spot.

[FarmerJon]

Personally I couldn't see a good reason to switch to 12v, other than everyone says you should, because 12v. 

I would try to o see if your area has some old-timer that can still rebuild your generator for reasonable money. Maybe ask at the farm supply store or Napa. 

You might find someone who will help you for very little $$.

Or, look into switching to one of these 6v, positive ground, alternators and enjoy the actual benefits without all the bother of hacking all your gauges and radio. 

 

https://www.ebay.com/itm/New-Delco-Car-Truck-and-Equipment-6-Volt-Positive-Ground-SE-Alternator-/265382495146?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=711-127632-2357-0

 

Disclaimer: seller is random, not actually sure of quality or if this particular one would be a direct fit, just here for price reference. I would expect to at least need to swap pulleys.

Edited February 2, 2022 by FarmerJon

[Sniper]

34 minutes ago, FarmerJon said:

without all the bother of hacking all your gauges

 

There is exactly one gauge, maybe, that needs addressed.  The fuel gauge and on a 46 Plymouth that doesn't apply.

 

Everyone isn't saying switch to 12v because 12v.  I switched to 12v because I am going EFI and I plan to run AC, something 6v will not accommodate. 

 

So if you are going to make claims at least make honest ones.

 

As for the wiring, if your existing 6v wiring is good then it is more than adequate for 12v use.  If it is not good it needs addressed regardless.

[FarmerJon]

42 minutes ago, Sniper said:

 

There is exactly one gauge, maybe, that needs addressed.  The fuel gauge and on a 46 Plymouth that doesn't apply.

 

Everyone isn't saying switch to 12v because 12v.  I switched to 12v because I am going EFI and I plan to run AC, something 6v will not accommodate. 

 

So if you are going to make claims at least make honest ones.

 

As for the wiring, if your existing 6v wiring is good then it is more than adequate for 12v use.  If it is not good it needs addressed regardless.

Sounds like you have a good reason to switch. 

But I don't think EFI is on most people's minds when they make the switch.

I am not saying it is bad to switch, just have a reason.

I don't have a reason.

OUTFXD sounds like he is financially stressed by the swap, to the point of possibly stalling the project. I am just offering an alternative opinion. Playing devil's advocate is what I do. Not trying to bust anyone's balls.

 

Also, did '46s not get blessed with a fuel gauge?

Edited February 2, 2022 by FarmerJon

[Sam Buchanan]

5 hours ago, OUTFXD said:

a full 12v conversion complete with rewiring, modern Fuse box, Electric fan, Electronic Ignition, and LED bulbs is underway.  However this is quite costly. Repairing the existing equipment is not AS costly,  but still not cheap and would push back the planned upgrades due to lost financials. That and I am hesitant to replace something that is going to have to be changed out soon anyways.

 

This puts me in quite the rough spot.

 

Your list is a set of "wants", not "needs". If you are wanting to drive your car with minimal expense your upgrades are not necessary since the old-school 6v system with points, and the mechanical fan will get you down the road very reliably when properly maintained. But an alternator is the key to having a 6v architecture with the advantages of a modern charging system. The battery stays fully charged at all rpm, the lights stay bright in city traffic, the troublesome regulator is history, and the alternator requires no maintenance. No brainer.

 

My 6v alternator is from this vendor:

 

https://www.ebay.com/str/HowardEnt?_trksid=p2047675.l2563

 

Upgrade the battery and starter cables to complete the refresh of the 6v system.

 

https://www.batterycablesusa.com/1-0-gauge-battery-cables-0-awg

 

Edited February 2, 2022 by Sam Buchanan

[Sniper]

3 hours ago, FarmerJon said:

Also, did '46s not get blessed with a fuel gauge?

 

Don't believe I said that.  Why don't you go read up on how the fuel gauge works in a 46 and you'll see why the voltage fed to it doesn't matter.

[Los_Control]

11 hours ago, OUTFXD said:

1 lead to ground, the other to the ARM terminal and got 4.3 volts.

Did you have the engine speed adjusted as Greg suggested?

At idle a generator does not produce much, needs to have more rpm to activate it.

5 hours ago, OUTFXD said:

a full 12v conversion complete with rewiring, modern Fuse box, Electric fan, Electronic Ignition, and LED bulbs is underway.  However this is quite costly. Repairing the existing equipment is not AS costly,  but still not cheap and would push back the planned upgrades due to lost financials. That and I am hesitant to replace something that is going to have to be changed out soon anyways.

 

This puts me in quite the rough spot.

If your wiring is ok, you can use it with 12 volts. And add in a new wire harness later.

Just saying a new wiring harness is not a requirement for a 12 volt conversion.

 

You will need to switch all your bulbs, the heater fan will run really fast on 12v, will want to correct that.

Your distributor will work with 12v, can do electronic ignition upgrade later.

When I ordered the new tank & sending unit for my 49, I told the nice lady I was still 6v positive ground. She informed me the sending unit does not care.

 

For me price does matter. I have heard $150 for others to get a generator rebuilt. Then the price of a voltage regulator.

Couple years ago, A 1 wire GM alternator from napa was $45. The difference in price will pay for all your bulbs and enough leftover for lunch.

Maybe now is the time to convert to 12v if you do plan to go that route anyways.

 

[Kilgore47]

I replaced the generator on the 47 P15 with a 6 volt positive ground 60 amp alternator about 6 months ago.  The new alternator and universal bracket cost about the same as rebuilding the generator.  Then I would have had to address the voltage regulator.  It was cheaper to go with the alternator.  Now I don't have to worry about it.  Still have the generator and it works.  The wires inside are burnt and the front bearing needs replacing.  I don't have the knowledge to remove the front pully without breaking something.  You don't have to change the pully on the water pump.  Just order the new alternator with the correct wide pully.

[greg g]

The charging system as engineered is there to replace power expent by the battery.  If your battery is new and fully charged, and your car starts easily with just a few revolutions, there is no charge being called for, so generator output at idle would be near nothing on a properly regulated system.  At full potential the generator  can probably put out 7.5 volts give or take above idle.  But this would only be needed with a marginally healthy battery and a high demand. Doing the grounding the field test, you should see a full charge via the Amp gauge, but increased rpm is needed.

[OUTFXD]

Addressing the comments all Willy Nilly.

 

The car has been entirely rewired with radio shack grade wiring and (Poorly applied) crimp on connectors.  Who ever did the soldering was of questionable skill.  I replaced the fuse box because the mountain of solder on the back was  grounding against the firewall. Much to my dismay,  there still appears to be a short in the system.  and who knows what connections are valid?  The wiring is beyond saving and needs to be replaced.  That is the reason behind my having a new wiring harness installed.

 

I have already upgraded to 1/0 gauge battery cables. Starter wires. and had the starter professionally rebuilt. Considering replacing the starter solenoid as the starter drags with anything less than 12 volts applied even with a fully charged battery. so I suspect someone slipped in a 12v solenoid.

 

I plan on going to a 12v electrical fan and LEDs as I have heard bad things about 6v varients. This will remove strain from the engine (The electrical fan alone is worth upto 30 horsepower in parasitic drag.  On a 100 hp engine that is near a third of the engines power just turning the fan)  and hopefully promote efficiency.

 

Engine speed.  I dont have a Tachy-o-meter so I am unsure what the engine RPM was where I tested it.  I did bring the RPMs up slightly with the "Throttle" control. I will test again later with higher RPM.

 

I apologise  if my comments are unclear of poorly formed. I am a stroke survivor and sometimes find it difficult to put my thoughts into words.

[BobDeSoto]

Years ago Dad owned a couple of 1950 DeSotos.  He used to throw in an 8volt battery in the winter.

Never turned out  good!

[desoto1939]

outfixed: do you have a service manual for your car. In the service manual there isa a wiring diagram that will show you how each wire is routed to the various other components.

 

I would suggest that you prchase one it does not have to be a factory one can be a reproduction.  If you had the manual it would have indicated the F and A wires adnto where they would connect to on the voltage regulator.

 

Rich Hartung

desoto1939@aol.com