Starting a new thread. Good place to rant about electronics. I had charging problems a couple of weeks ago, replaced alternator and voltage regulator and had this running great. But, I did not have a voltage regulator connector. The old one had crumbled apart over the years as the plastic degraded, so I had cut each of the wires and put a spade terminal on them. So just wanted to clean it up and make it look a little nicer, I bought a new connector. Decided today was the day to wire it in and now I have nothing!

The way I DID have it wired with the spade terminals was like this:
I - green, goes to dash inside
A - yellow, goes to BAT on alternator
S - white, goes to STA on alternator
F - black/red, connected to ground on the regulator housing.
(please note that prior to this, the alternator had my white wire on FLD terminal, so when I replaced alternator I had corrected that)

Putting on the new connector, I ran everything the same EXCEPT the black/red FLD wire. On my car originally the lead from the alternator grounded to the body of the voltage regulator, where it screws to the radiator support. In following diagrams I found online, I removed that connection and ran the red/black wire from alternator directly to FLD terminal on voltage regulator.

I got no power from the alternator, was not providing any output. So I decided to put it back the way it was, I put ring terminals on the two FLD wires and connected them to ground. Still nothing. This is electronically speaking exactly the way it was an hour ago, but now I have nothing.

With engine running:
I - 11.56 volts
A - 11.75 volts
S - 0
F - (ground)
At the battery, 11.75 volts

With engine off, battery shows 11.8 volts.



Stock photo of a 1G (1965-1983). This lets you see what the terminals are labeled as.

BAT - BLK/YEL (connection with rubber cover, you can see a little red around edges) FLD - BLK/RED (right next to BAT, no cover, shiny bolt) STA - WHT (farthest away, rubber cover)

Why did I "fix" something that was already working?!

 

John dose the car have a Guage or light for charging?
On the trucks they are wired differently and why I asked.

Going to bed now up at 3am but when I get home late from work I can see how my truck is wired, it has a Guage.
Dave ----

 

My car has the gauge, and I just found out that they were wired differently. I had book-marked some threads to read later on tonight. But I can say this, with nothing on FLD (on alternator) except a jumper going to the battery, I still only get 11.7 when the engine running, and I think based on what I have read is that this means the alternator is dead. Going back to the way I wired it, and the smell I described to you, I am now thinking I wired it wrong and burned it out over the course of a week or so. But it is under warranty still so I will have to remove it if this is the case.

 

The big red stud BAT should have a 10 gauge wire and goes to the starter relay that the cable from the battery is on. This is the ALT out put to charge the battery.

I think and this would need to be checked, the field stud goes back to the regulator as power to it tells the ALT to turn on and work.

On my truck the stator, S stud, goes to the choke to help it open. This can be left with nothing on it. This is a 2nd ALR out put at half volts of the battery stud.

I would need to check the wiring of the regulator to make sure but think the "I" is left empty when a Guage is used?

F or field would be from the F stud of the ALT.

1 of the other 2 is a power on with key to tell the charging system the motor is running and should be putting out volts.
The other is a sensing wire and would get tied into the main power wire feed to the car or back to the starter relay to know what volts the battery is at so the regulator can adjust the ALT output to keep the battery charged..

Again would need to check on the regulator wiring to make sure of it..

Yea if power to the field stud and nothing out of ALT it sounds bad.
Dave ---'

 

I just removed the alternator so that I can take it to be tested later. I think when I have a new one (or verify this one is good?) I will put the voltage regulator wires as black F to white FLD on the alt. The color codes are throwing me off, but since STATOR is not used and the black/red is definitely ground (grounds 2 places on one end, engine block and alternator, and grounds on the other end to regulator housing) it is not going to be used to go to the voltage regulator housing at all.

I don't know why I have green going inside the car if it is not used for an ammeter car, only for a dummy light setup (1965 and earlier I think). But since it is there and was previously in use I might as well reconnect it. At any rate I have to figure this out today or tomorrow so that I can do the show on Saturday, because Friday I will be gone all day down to Burgaw to help my son-in-law build a shed.

 

Could thst green wire be the power on wire?
I don't think I would go by wire colors if they don't match up to what you found on the web but go by where they start & end at.

I cont remember if I made a note of how my truck got wired or not as mine had 3 different color wires splice together to reach where it needed to.
I will Also try and search the web to see if I can see how it should be wired when I am off loading here at work.
Dave ----

 

The green one goes from the voltage regulator cluster, back around the front, the joins up with the cluster of wires for headlights and blinkers and all goes back into the cabin together. I think Ford would have used the same wiring harness regardless of which instrument you have, so maybe where the green wire comes out it is unused.

I just came back from Autozone where the alternator tested GOOD. Quite surprised as it failed my "field test". He tested it twice just to appease me, got the green check mark both times. So now I am beyond confused.

 

That is strange if you put 12 volts to the field stud on the ALT that it did not go full output?
Or did you put 12 volts to the field at the regulator because it was easy to get to??
If that wire is broken then it would show as a bad ALT when full field testing..
Wish I had normal working hours so I counder come look at it. Right now I don't know what time I will get but some time after 6pm and have to be on the road for work at 4am for a 7am drop in Newport NC.
Dave ----

 

Yes, 12v directly to the stud at the back of the alternator. Essentially Autozone does the same thing with their tester, and it passed with flying colors! My jumper may not be all that great, especially if this requires some amount of amps to pass through it. But I definitely got a little spark when I connected the other end to the battery cable.

In regards to the voltage regulator, the green I wire has always been called "indicator" in the diagrams I've seen, but earlier today I saw one that referred to the I wire as "ignition" and explained that this wire comes from inside the car and is keyed hot. So I tested that, sure enough 0 volts with key off and 12v with key on. It was said that this wire is what tells the voltage regulator to begin working? At any rate, with key on and engine running, at the voltage regulator I have 12v at the green wire, I have 12v at the yellow A wire (which goes to the battery connection on the relay), and 0 volts on the stator (not used anyway) and also 0 volts on the field. My understanding is that with 12v to green the field wire should be showing 12v also. So I worked under the assumption that maybe the voltage regulator is bad. Removed it, when I shook it I can hear something rattling inside, so I took it back to Autozone. By the way, sniffing the voltage regulator I could definitely smell that "electronic smell" I was telling you about. The guy at the store says no problem, he will replace it free since I just bought it. Gave me another one, not exactly the same one, I think I had previously bought the $34 one and the only one he had in stock was the $31 unit. One was electronic and one was mechanical. I took the one he had in stock and got a candy bar to even things out. Installed it and STILL no charge from alternator, and still 0 volts at the field wire.

So now I am more lost and confused than ever. I have an old GM style 1-wire alternator somewhere around here, if worse comes to worst I will go digging for it and install that, convert myself over. I was trying to avoid it since the factory setup has worked so well for so many years.

 

Hey peoples.

 

I keep hearing showers over the weekend what if we call off the show and both look into that no charge on Saturday?
If that works let me know a time you want me there and see if we can't fix it.
Dave ----

 

Howdy Shawn!
Hey Dave I have some news. First, I just spoke to the Four Oaks Chamber and they have canceled the show due to rain forecast and plan to reschedule it for April 2022.
Something you said yesterday, when you asked me if I was checking voltage on the FLD terminal behind the alternator itself, or over on the voltage regulator, kept gnawing at my mind. I had that EUREKA moment - why am I looking at output voltage on the battery when I should be looking directly at the terminal on back of the alternator. So I checked this, and I have 14.4 volts there. Perfect. Except that I have fried my new voltage regulator by grounding out the FLD terminal in one of my many attempts to "try this and see if it works". I have always heard there is a fusible link between the alternator and battery, and since my new alt is 65 amp and the old one was 38 amp, maybe that caused it to blow. This is what I found when I took off the wiring loom and unraveled the electrical tape.


I thought I was on to something when I realized one of my multimeters shows 12.2 at the battery while the one I had been using only shows 11.8 I thought maybe everything had been working the whole time and my voltmeter was faulty?

But with engine running they both show less than 12, so obviously this was not the solution.

The first thing I unraveled turned out to be a yellow wire near the solenoid. It was completely corroded in two. The yellow wire still shows 12 over on the regulator, but it splits before it reaches this point, so whatever this leg went to has nothing. Maybe that is why my ammeter doesn't work.

When I unraveled the next bulge, I found the problem! This is the 10 gauge black/yellow wire that goes from the alternator to the battery terminal on the solenoid.

As I unraveled more of the tape, you can see how bad it is. Completely corroded and the connection totally gone.

 

That dose look bad LOL
The fuse link would be on the ALT out put 10 ga wire going to the relay.
I am happy I pointed you down the right path to check the wires

If you have not made permanent connections might try safe temp (so it will not short out) connections to see if it will charge.
I have some butt connectors that has heat shrink on the outside that should seal the connections once you get back to good wire.
Or back to good wire and solider and heat shrink as I have that also.

I was lucky today my 2nd load was canceled so I am home, just need to run the trash to the dump.
I know you said Friday you are helping your son but I get my needle in the eye and will be out of it till after noon as it should be safe to move around.
Let me know maybe text me if you need help on the car.
Dave ----

 

Thank you for the offer I may take you up on that, if I don't finish it up today. I am halfway through but my friend in Angier just texted me, he sandblasted and primered some parts for me and I have to go pick them this afternoon because he is going out of town for the weekend, leaving this evening.

Meanwhile my son-in-law texted to say Friday is off, due to rain they have not dropped off his shed kit yet, and even if they did it is supposed to rain all day tomorrow so it looks like we are washed out. Just went from a busy Thursday / Friday / Saturday to nothing going on, except sitting around watching the rain.

I bought an in-line fuse holder to use in the new connection I am putting in to replace the corroded area. But the biggest fuse they had (ATO type) was 40amp. They have MAXI fuses that are much higher, and in fact I have a bag of 120 amp MAXI fuses, but they don't sell the inline fuse holder for them.

 

I checked my truck when I got home from the trash run and I have a 14 ga fuse link wire in the line from ALT out put to the relay to protect the ALT.
I did not look that close at the other fuse links on the truck to see where they go, sorry.

The thing about using a normal fuse over the fuse link is the fuse can / should blow as soon as the ALT starts charging because of a spike it puts out to start charging.
So if the MAX out put of ALT is 60 amps you would need a fuse of 60 amps but when the ALT first starts it may go a little higher and blow the fuse.
The fuse wire link is what they call a slow blow fuse and can take that spike till the ALT settles in to its normal out put.

I am free after noon on Friday as my eye should be ok for me to do things and anytime on Saturday.
I may have to work on Sunday if they call me.
Text me if / when you want me to help
Dave ----