Alternator gauge question

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Right now I am showing 1/2 Volt drop at Ballast resistor and at both Field wires on Alt. Am I correct saying that if the Voltage Regulator Is good then I shouldn't see more than 14.5 volts charging??
 
1/2 volt drop is obviously a LOT better than you had, but you are still loosing some someplace.

Did you pull the bulkhead connector apart and look it over? If either the main battery feed going IN or the dark blue coming OUT (into the bay) are loose/ damage, that could account

Now that you've got that done, you could also check at the ignition switch connector and see what you have into/ out of the switch, which should give you "where" you are losing the last 1/2 volt.

It might not sound like much but at 12-14V, 1/2 volt is a pretty large percentage.

Great, tho, sounds like you made some marked progress!!!!
 
1/2 volt drop is obviously a LOT better than you had, but you are still loosing some someplace.

Did you pull the bulkhead connector apart and look it over? If either the main battery feed going IN or the dark blue coming OUT (into the bay) are loose/ damage, that could account

Now that you've got that done, you could also check at the ignition switch connector and see what you have into/ out of the switch, which should give you "where" you are losing the last 1/2 volt.

It might not sound like much but at 12-14V, 1/2 volt is a pretty large percentage.

Great, tho, sounds like you made some marked progress!!!!
I know I am losing about .2 V at the electric choke. Not sure if it's wired right but it's getting power from the Alternator field wire I believe. I will check all the Interior stuff for Voltage drop this afternoon as well as pull the Bulkhead connector. I may just bypass the Alternator gauge while I'm at it.
 
You've gained a LOT of ground, and I'll bet you feel a little better about diggin' around in there
 
You've gained a LOT of ground, and I'll bet you feel a little better about diggin' around in there
Slowly but surely. The + field wire was down to one strand. Fixed that & started digging in to the rest of it. I'll post up what I find. The great thing is I finally understand Voltage Drop & how to test for it. Thanks to you Del & everyone else for the help.
 
You have to power the electric choke by a relay. You can use the field wire as a trigger, but draw power to run the choke from the battery, or ¼” stud on starter relay.
 
You have to power the electric choke by a relay. You can use the field wire as a trigger, but draw power to run the choke from the battery, or ¼” stud on starter relay.
Thanks for that. I'll have to fix that for sure.
 
After getting the voltage drop down to .4 volts(.2 w/ Choke disconnected), I started it up and now I am not charging at all Just Battery voltage while running at any RPM's. I am pretty sure based on the symptoms before that the Alt. was somehow full fielded. Before, the higher the Rpm's the more Voltage that was being put out. I have a solid ground at the VR but did not check it with the car running yet.
 
This is surely right in the regulator circuit, or alternator field, or a bad regulator

You may, for example, have damaged the brushes or slip rings by running it for a length of time "full field

The regulator is simple. The regulator "I" terminal not only powers the regulator, it acts as the reference voltage --the voltage at which the regulator "looks" to see if the output is correct

So if the "I" terminal is not getting power --bad connector, corroded, or bad regulator, no charge

The regulator controls field current by controlling "the amount of ground" on the green wire, IE field current is fed by the blue field wire, and the regulator controls the green field lead to ground

To start checking, I would determine the blue field wire, and leave it hooked up. UNhook the green field wire (which goes to the regulator) and clip lead it to ground

With key on, confirm that you have solid battery voltage to the blue. Running the car should act nearly same as your original problem, IE too much charge and increasing amps as RPM goes up

IF THAT happens, it has to be either regulator wiring or bad regulator

IF THAT doesn't happen, check the brushes for continuity between the two, and should have NO continuity to ground. Various books over the years change, but the field should draw (full battery voltage, or "full field) up to about 3A

IF it DOES charge "full field," check out the regulator wiring

One way to do that is to reverse the function of the regulator wiring. Just like voltage drop, checking wiring works much better UNDER LOAD to show up troubles.

So...........

Unhook the blue field wire, and clip that terminal to ground. Unhook the regulator, turn the key to run, and jumper between the two terminals in the regulator connector. Also visually inspect them for corrosion, looseness, etc.

What you have done is to "full field" the regulator using the regulator wiring. Check as before for a "full field" output, making sure you are actually getting "good battery" voltage AT THE GREEN field wire this time.

If the above checks out, replace the regulator.

Dual_Field_Alternator_Wiring.jpg
 
Thanks Del:

I ran these tests and got these results.

First I I removed green wire and put test lead from ground to the terminal on the alternator and just left the green wire hanging. It charged at over 16 volts at about 2k Rpm's.

Second I hooked the green wire back to the Alternator field terminal. and unplugged the Blue wire. I connected my test lead from ground to the blue terminal. Is it safe to call these pos. & neg. Field terminals??
I then unplugged the VR and jumped the 2 wires together.
Now I had over 16 volts again at around 2K Rpm's.

Then I hooked everything back up properly and started her up again. Now I am running Full Field again. :banghead:

So here's where you're gonna want to slap me. I unplugged my Edelbrock electric Choke and she charges between 13 and 14.2 volts based on RPM.

I must have tapped into the wrong wire for my Choke. :oops:

I have power to the choke coming from the blue wire and I was getting ground from a black wire coming out of the taped section of wires going to the alternator. :wack:

I believe it's possibly connected to the green field wire but I'm not sure. On this car the wire going to the Blue Field is actually black due the the PO's rewiring job which has made this confusing for me. I will wire the Choke Neg. directly to ground and then figure out the best power source for the Red Choke wire.
 
Charging system is all fixed. Choke is properly wired now with ground straight to engine block. No more than .2 Volts Drop. Now back to the Dash lites not working. Thanks again for the help and education.
 
!! LOL !!! Believe me, these "life's lessons" is stuff "we" never EVER for get!!
 

Amen! The old me would have put a new Regulator in days ago. But now I want to start fixing stuff right instead of guessing and throwing parts at it. I have only put 50 miles on this car since I got it last October. It's come a long way and I feel safe to drive it anywhere now.
 
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