Voltage

V8 and bob showed you 2 ways to do it.in both cases you need an exciter wired to alternator to have it put out amperage.the bulb is needed to act as a diode otherwise the alternator will not allow you to shut off engine as without diode it will energize the ignition.leaving you with a complete circuit from alternator to switch and back in a continues circle
 
I thought Oreilly's checked the voltage ay the battery with the engine running, and the voltage was over 14 V ? That would tell me the alternator is charging just fine, and there is some other issue on why the voltage gage never changes. No Einstein info from me, but seems like common sense.

Sal
 
Sorry, I re-read the first post, and only the battery and alternator were bench tested at O'Reilly's. Never mind what I said above.

Sal
 
Seems like from what I'm reading on the posts is that the only thing I am missing is a wire from the ignition switch (when keyed on and off) to the #1 spade on the alternator with #194 bulb in between. I think bulb should only stay on for a second until car starts and then should go out. If it stays on, guess the alternator is bad. I guess all my other wiring the way it is, is okay. If I missed that, let me know.
 
Oilslickwillie said:
Seems like from what I'm reading on the posts is that the only thing I am missing is a wire from the ignition switch (when keyed on and off) to the #1 spade on the alternator with #194 bulb in between. I think bulb should only stay on for a second until car starts and then should go out. If it stays on, guess the alternator is bad. I guess all my other wiring the way it is, is okay. If I missed that, let me know.
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Thou are nearly there. Without the indicator light the alternator will charge but it won't correctly as the light acts as a voltage sensor for regulation. The light should have been connected to the white wire on your plug. The plug is correctly wired and should loop the red to the battery positive terminal. A wire of sufficient gauge should then be connected from the battery positive terminal directly to the battery positive terminal. The output of the alternator should not be routed to the ignition switch or anywhere inside the cab unless you have the battery in tbe trunk.
From what i can make of what you have written it would appear that either the ignition is fed from tbis existing cable or it is going to your voltmeter. Either way it is incorrect. The wire is unnecessarily long and may be of insufficient wire gauge compounding your problem.
Hope this helps. The circuit that i think Bobs 396 posted is the way it should be connected.
 
Instead of a bulb I've seen a resistor inline with the exciter wire. My car uses an after market gauge set, I'm not using the dash indicator. My guess is that my volt gauge has something built into it or the exciter wire has something in the fuse block I can't see. I'm using an after market harness.

The link below is good and should help, it gives the part number of a Radio Shack resistor if you want to bypass the idiot light. Photo is at the bottom of the page.

http://www.darren-criss.org/three-w...ternator-wiring-diagram-366e429ef13c080d.html
 
So here's the latest.
I wired a new plug for the 2 spade connections on top of alternator. Pigtailed the red #2 wire to back stud on alt. Wired a #194 bulb and socket between the #1 white wire and the starter selenoid. Light did not come on when car was started.
Next, decided to try and trace the red wire on stud at back of alternator that was coming from under dash. That was hard, could hardly get under dash to find it. When I did, it was not connected to anything which means car was running off battery only.
So, I disconnected the no nothing wire and ran a wire on battery side of starter selenoid. Started car and the exciter light flicked on/off for a second which I believe it is suppose to do. Volt gauge reads 12.5 to 13 at idle. When I revved the engine with more rpm,s the volt gauge reads 14.5.
Only problem is that when revved up the excited light comes on and stays on. If you turn car off and restart and idle, light comes on/off for a second. If revved up, light comes on, stays on until turn off ignition. Car seems to run good, drove it around block okay. Is this something to be concerned with or is this okay?
NEW PROBLEM: Car idles good for a few minutes then acts like it will die, then runs good again. If holding down accelerator pedal very slightly, it will not act like it is going to die. Guessing it may need carb adjustment, carb cleaning or shot automatic choke problem. After I feel alternator problem is solved I will tackle running problem.
 
Forgot to mention, I wired the exciter wire with bulb onto the small stud on the starter selenoid, I believe it's marked "s". Should I have attached to the other small stud on starter selenoid? Guess I'm thinking that may work better.
 
Oilslickwillie said:
Forgot to mention, I wired the exciter wire with bulb onto the small stud on the starter selenoid, I believe it's marked "s". Should I have attached to the other small stud on starter selenoid? Guess I'm thinking that may work better.
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The 'S" terminal on the starter solenoid is only for the Start wire from the ignition key switch.
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Should the exciter wire connect to the other small stud (I) on the starter selenoid instead of the "s" stud.
If not, where do I need to attach it.
 
I was told that my #1 wire on the alt. just needs to be connected to a switched 12v source. If that's correct it would not have to go to the starter selenoid, I could attach from my switched 12v block to the #1 stud on alternator. This person even said I did not even need the idiot light or even a diode. Am I close on this one. Just need to know from end to end of #1 wire where the connections should be?
 
Google some 3-wire alternator images. I've seen some exciter wires that go to the ignition switch, can't recall the position.
 
Oilslickwillie said:
.... decided to try and trace the red wire on stud at back of alternator that was coming from under dash. That was hard, could hardly get under dash to find it. When I did, it was not connected to anything which means car was running off battery only.
Click to expand...
Be sure to thank the person who installed the alternator, with lots of words you can't use in mixed company. Lesson learned: don't assume someone else did something correctly.

Oilslickwillie said:
Should the exciter wire connect to the other small stud (I) on the starter selenoid instead of the "s" stud.
If not, where do I need to attach it.
Click to expand...
Not on the 'I' terminal of the starter solenoid, it only has power on it when the starter is cranking.
.
Oilslickwillie said:
I was told that my #1 wire on the alt. just needs to be connected to a switched 12v source. If that's correct it would not have to go to the starter selenoid, I could attach from my switched 12v block to the #1 stud on alternator. This person even said I did not even need the idiot light or even a diode. Am I close on this one. Just need to know from end to end of #1 wire where the connections should be?
Click to expand...
Look back on page one of this thread for the post from V8 Bob with a wiring diagram / link. The wire to terminal #1 should come from a terminal that has 12v on it when the ign key switch is in the 'run' position.
If you can run it from the 'Gen' light in the dash that would also match the same wiring diagram.

.
 
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Thanks Dmsfrr,
I just looked up some 3 wire diagrams. Guess I missed this earlier. Looks like I need to come from #1 on alternator and just find a 12v source that is hot when the key is on. I have my car with a hot block when keyed on so I think I will try and connect there. Would be the same as connecting to ignition switch but a lot easier to get at. Probably should carry an extra #194 built in case it should burn out for some reason. Thanks for your help and hope I finally get it right. I also heard it's better to not use a pigtail on back of alternator but to run #2 back to hot on starter selenoid.
 
If this is an example of the work done by a previous owner, or their favorite shop, double check virtually everything. :(
 
That's what I'm in the process of doing. So far I have just about fixed or replaced everything on this car. It's looking good though but I've put a lot of time in it and have done it all myself, even with an old Vietnam neck and back injury. You should have seen the wiring before I started, alternator is the last of it though.
 
Finished changing the #1 wire to a 12v keyed source with the #194 bulb in between. Volt gauge reads 14.5 volts. I'm by myself today so could not watch bulb under the hood when starting car but when I got out to check with car at idle, I had a very small flicker in the bulb. When I revved the throttle, the bulb goes out. Could not think of anything else but believe I will change the #2 wire pigtail from the stud at back of alternator and move it to the hot side of starter selenoid. I know some say this is better with less resistance than using a pigtail so guess I'll try that. Do you feel I finally have it whipped?
 
You have it whipped, so why are you going to move what you call the #2 wire? ...and why are you fooling around with an idiot light if you have a gage? Just eliminate the light, declare success and move on to something else. Leave the #1 wire connected to the ignition post on the switch. You are way over thinking this thing.

Just my opinion and worth every penny you paid for it. :-)
 
Motorhead6 said:
You have it whipped, so why are you going to move what you call the #2 wire? ...and why are you fooling around with an idiot light if you have a gage? Just eliminate the light, declare success and move on to something else. Leave the #1 wire connected to the ignition post on the switch. You are way over thinking this thing.

Just my opinion and worth every penny you paid for it. :-)
Click to expand...

The #2 connection is the regulator voltage sensing circuit. It provides the 14.4V or so output to the voltage distribution site, not just to the back of the alternator. This eliminates/minimizes any voltage output drop.
The #194 idiot light will warn you of a alternator problem that won't show on a volt gauge, along with positive shut down when the exciter wire is off.
Oilslickwillie is trying to wire the alternator correctly and as designed. No over thinking. :)
 
V8 Bob, I don't like things half done so according to your instructions, and it's working good now thanks to your instructions. Only reason I moved the #2 wire was because I was having a flicker in the exciter light after starting car. From someone else's suggestion I undid the #2 pigtail and wired back to + side of starter selenoid. That eliminated the flicker, it was just so small you can barely see it. With a tiny rpm increase that is minimal, hardly noticeable the flicker is totally gone. Light goes out. Volt gauge with engine off shows 13+ volts. With engine running and revved a little, goes to 14.5 volts. I think I am going to call this finished. When I have time, I may move idiot light to dash. On to the next project. Thanks V8 Bob and those who gave me informative advise.
 
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