I'm hoping Mike is reading all this. He is the guy who was having problems with his regulator and getting his Alternator to charge (and also wanted to run the wire from "F" to battery)

MIKEY Are you there?

 

Alternator Diagnosis Worksheet try this link helped me check a "in the end a bad alt Tim

 

Hello Dave and Dan,

I have been in the garage working on the 56.
Needed to go through and make all of the connections as I just redid my instrument panel and installed all of the wires and new bulbs..
Please let me just say that it is not that easy for me to just bring the truck to a place and have them clip on to the battery terminals to tell me if my battery and charging system is working. It will not make it there.. and I still have a lot of work to make it road worthy.
But here is a few facts that I have found out.
I bought a new electronic voltage regulator and removed the old one.
It still does not charge the battery.
When it is running and I quickly remove the pos. terminal the truck dies.
Now if I put on an old style point type of voltage reg. the battery shows a charge..and it stays running when I take off the pos. terminal from the post.
What could be going on here?
The electronic volt reg. came with the truck with all of the new wiring installed when purchased.
And it was noth charging the battery back then for the guy I bought it from..but it was only started a few times.
Still I have a slight twinkle of a spark at the neg. terminal when I hook it up.

 

Hi Mick,
I'm not quite sure of the kind of system you have but I gather it's one of those older Ford alternators that used the electromechanical regulators when it originally came out and the electronic regulator is one of those solid state replacements that came out a few years later. As I understand it, when you use the older regulator it will charge and keep the engine running when you pull the positive battery lead. I am thinking it could be one of two things that cause it not to charge or keep running with the electronic regulator. It could be that the solid state unit is bad or needs an extra sensing lead to the battery. Is it a screw terminal type or does it have several flat spade connections that a plug in connector goes on? If so how many connections does the electronic regulator have and how many does the old one have. Are the connections marked and if so how. If you can get pictures of this stuff send them. You can e-mail them directly to me at db1@pvpmedia.com

 

Hi Dave,
Yes both the electronic one that came with the truck, and the old(new in Box) point type have the spade connectors that the wire bus just slides right on to both units. (I,A,S,F)
and the ground wire from the harness is ring bolted to the right inner fender well.
Maybe that is the answer..that the alternator on the 302 (alternator just has Motorcraft on it) is old and does not jive with the electronic volt reg.
So it does now charge with the old point type volt reg. and stays running when pos. terminal is disconect.

But it is the sparking at the neg post that worries me..I have not left the neg terminal on over night or all day...yet..to see if the battery drains down.

It is just that in the wire harness instructions that came with the truck..specifically mention to look and see if the neg. term makes a spark..if it does..some thing is drawing power.
But I have nothing but a light switch,blinker and ingintion. No interior light or radio..yet.

Someone mentioned a diode in the alternator..but it is now working with the different volt regulator..and I am wondering why>

 

Hi Dave & Mick,

Dave I'm gonna let you look into this one. Poor Mick doesn't need two sets of input - I'm gonna watch though to see what comes up. I fyou need anything I can help with let me know.

Mine did this same thing and with the motorcraft alternator, an amp gauge and the electronic regulator. The 66 Ford manual I have shows that set up wired the same as a Merc not a Ford.

If you need the diagrams, let me know. It's fairly different.

 

Mick,
it's been a while since I worked with one of these. I had a 73 Bronco and a 74 Econoline, both with 302 engines. I remember some weird stuff about the Bronco where it had a heater on the automatic choke bi-metal spring in the side of the carb that was powered from an output on the alternator. I don't have any documentation on it now but I remember it being a problem related to the alternator and regulator. It was intended to replace the old heat tube that used to come from the exhaust to get the bi-metal spring to wind back and take off the auto choke after start up. I think the idea was to have a seperate line from the alternator heat the spring. It would have the same effect as the exhaust heat but be cleaner and only present when the engine was running. I think it was an idea that was short lived as I don't remember it being on the 74 van. I am not sure what year stuff or combination of stuff you are working with but this couild be part of you problem as it seems that coil had to be in the circuit to be working right. That was over thirty years ago and at 63 I can't remember everything. I would suggest you try and find some documentation from that era and look at some circuit diagrams.

About the slight spark from the negative terminal. I am assuming that this only happens when the positive terminal is still connected. If not, it's a real puzzler. I remember an old 63 Fairlane station wagon my dad had that had a similar problem. We finally traced it to a resisitve path to ground in the old pressure type brake light switch they used to use. It was mounted on the master cylinder. It didn't cause the brake lights to be on and it still worked when you hit the brakes. Of course if you only get that spark when the electronic regulator is being used it's a pretty good indication that the regulator is the problem. If you can, find another electronic regulator and give it a try. One that you know is OK.

Dan may have some diagrams that would help here. If I get time and figure out where to look I might find something online but I expect you would probably get to it faster than I can. If you can, disconnect all wiring beyond the alternator and regulator circuit and see if you still get that spark. It really still sounds to me like a bad electronic regulator or a resistive path of the positive side to ground, (negative), some place in the wiring.

I realize this is a frustrating situation but I am sure you can whip it with a little detective work. It's pretty muck a cinch thst the alternator is OK if it works at all. Of course there may be some compatibility issue here if these parts came from different years and different systems. Worst comes to worst, you may have to stick with the old electromechanical regulator unless you want to upgrade to a newer kind of alternator.

 

Hi Guys!

I heard my name mentioned so I thought I'd post those two schematics.

The autolite drawing is th esame as the power point drawing I sent to Mick earlier. It's the basic ford diagram with the idiot light.

But in looking into this, I discovered the Mercury wiring diagram with the AMP gauge wired in and it's pretty different as you can see.

Dave, these are out of a 1966 Ford Shop manual if you need a time period. It also has great pictures of the regulators and some very involved drawings of hook ups for the charging system testing - about 7 pages of them. Let me know if you need any more, or want me to send them direct to you in a larger scale - Big Dan is watching!

 

Dan,
I have been looking over the diagrams you posted. I see the differences you mentioned. Even though the Ammeter is one of the differences I don't think it has anything to do with the other differences. In one case they are using the negative current path of the alternator output to bring in the field relay and on the other they are using a signal from the ign. switch. This would suggest that these two regulators are probably different part numbers as the one uses a current relay and the other uses a voltage relay. The coil for one would be wound differently than the other. I can see where this would pose a problem if you got the two mixed up.

What I really need to see is the diagram he is using and the diagram of the solid state regulator. Oh well, I guess we will keep banging away at this and try to puzzle it out one step at a time. I hope Mick has the time and patience for this.

 

The mechanical regulators used for the two systems are the same. For the system with the charge indicator light:



When the ignition switch is turned on a small amount of power is supplied to the alternator field through the indicator light and its shunt resistor. Once the engine starts and the alternator comes up to speed an AC voltage is developed at the stator center tap. This is used to energize the field relay. When the field relay pulls in the ignition switch and charge light are bypassed turning off the light and making full power is available to the voltage regulator.

In the system with the ammeter:



The ignition switch simply energizes the field relay which supplies power to the voltage regulator. This arrangement is used to limit the current load on the ignition switch. The regulator would work fine with the ignition switch suppling power to the "I" terminal and no connections to "A" or "S" but the ignition switch would need to carry the alternator field current.

On some vehicles the alternator stator terminal is wired to an automatic choke.

I have attached images of the electronic voltage regulators below. Different models were used for vehicles with indicator lights and vehicles with ammeters. The following is copied from a Motor Truck Repair Manual, 32 edition:

Some 1978-79 Ford vehicles are equipped with new electronic voltage regulators. These solid state regulators are used in conjunction with other new components in the charging system such as an alternator with a higher field current requirement, a warning indicator lamp shunt resistor (500 ohms) and a new wiring harness with a new regulator connector. When replacing system components, note the following precautions:

1. Always use the proper alternator in the system. If the new 1978-79 alternator is installed on previous model systems, it will destroy the electro-mechanical regulator. If the older model alternator is used on the new system, it will have a reduced output
2. Do not use an electro-mechanical regulator in the new system since the wiring harness connector will not index properly with this type of regulator.
3. The new electronic regulators are color coded for proper installation. The black color coded unit is installed in systems equipped with a warning indicator lamp. The blue color coded regulator is installed in systems equipped with an ammeter.
4. The new systems use a 500 ohm resistor on the rear of the instrument cluster on vehicles equipped with a warning indicator lamp. Do not replace this resistor with the 15 ohm resistance wire used on previous systems.

 

Outstanding Info!

One of the things Mick was doing was swapping back and forth, trying mechanical and electronic regulators. Low output and faint ground cable arching on connection were two of the concerns. The 78/79 thing looks familiar and maybe his problem in mis matching an older alternator with a newer regulator - throw in the amp meter clause as well. Now he will probably have a lot better luck getting the right regulator and checking the wire paths!

 

Thanks Dmptrkr,
You have posted what we need here. I see you mentioned the choke heater that was on some of the vehicles. As I mentioned, my 73 Bronco had that set up and it went heywire when the heater burned out. In turn, it took out the stock electro-mechanical regulator. I'm guessing that is why that system didn't last long.

Hopefully, Mick will glean enough information from this thread to cure his problem. It sounds to me like it is a matter of mixing the wrong components. That is why I always use a GM type single wire self regulated Alternator when upgrading old systems. It is a bit harder to do but it is simpler in the long run. Granted, it's not stock or original but it is far simpler in the long run if you can get around making special mounting brackets and finding the right belts and pulleys.

 

Hi Everyone,
Getting back to the subject here... I got a notice from a good source today that reminded me to mention them here. I don't know if any of you out there have dealt with this company but I have been very satisfied so far. They are an excellent source for all that automotive type electrical stuff we all need for our projects and their prices are decent. Check out Del City - Wiring Products and Professional Electrical Supplies and have a look around. They have about everything online and they will send you a really nice catalog if you fill out the online request form. I'll try to ad more of these places to this thread as they occur to me. I usually don't think of them until I hear from them or I need something.

 

Just returned from the garage.
And read all of the additional information posted..and I must thank all of you for your expertise. Thank you.
I went through much more additional work in trying to make the 3-wire system work.Took off the alternator and had it check out and it was fine..still I was given another one to try and I use both the new and mechanical volt reg. ..exactly the same senario as previuosly happened. Re checked all of the wiring and nothing was wrong except one thing..and that still did not make a difference. ( the one thing was that I was told on the solenoid on the fire wall that the battery cable should be on the side of the "S" little post..not the "I" wire little posts) My positive battery cable was on the side of the solenoid of the small "I" post I change that..and it made no noticable difference.
But now I may have put my tail between my legs on this one...
God bless the single wire alternator!
I was also given the GM single wire alternator as the last option..but to me this is the first option...
No sparks at the neg terminal on the battery when connecting and the alternator is now putting out 13.5 on the volt meter.
So it seems I have gone around what ever wire or issue I had with this new wire harness and the out side voltage regulator setup.
So far so good and everything seems to be working.
Glad I gave this a go..but also glad the single wire alternator option was there for me to use.

 

Your positive Battery cable should be connected to the post that has a 'B' by it. The one with the big lug and isn't going down to the starter.

And yes the one wire alternator was suggested at the begining of this.

Do you have a shop manual that has the year and make of your engine? If not, you need to get one, and follow the diagrams and instructions in it. If all else fails........