Alternator Full fielding..??

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67Dart273 said:
Whatever the drop is you measure will be added to the VR setpoint. So "if" the VR is not faulty it will want to charge about 14 when warmed up. If you measure 1.5V in the drop test, it will "run" the battery at 14+ 1.5 =15.5 V
Click to expand...
Ok, so I still need to look further due to it shooting up to the 18volt range. Swingn’
 
Swingn’71 said:
Ok, so I still need to look further due to it shooting up to the 18volt range. Swingn’
Click to expand...
The problem in this case is maximum current flowing though the rotor, aka full fielding.
You jumped ahead by not first determining if there is a ground problem in the field circuit. Perhaps not clearly stated, this would have been by checking for grounding with the field wires still connected to the alternator.
Mattax said:
Key off. Take a multimeter set on resistance or continuity. Put one probe on the alternator housing and backprobe each brush terminal.
Click to expand...

Regardless, you've now narrowed it to three possibilites:
The green wire is connecting to ground somewhere.
The regulator is causing it to full field because it is seeing low voltage (blue wire connection on the regulator)
The regulator is causing it to full field because it has failed internally.
 
Mattax said:
The problem in this case is maximum current flowing though the rotor, aka full fielding.
You jumped ahead by not first determining if there is a ground problem in the field circuit. Perhaps not clearly stated, this would have been by checking for grounding with the field wires still connected to the alternator.


Regardless, you've now narrowed it to three possibilites:
The green wire is connecting to ground somewhere.
The regulator is causing it to full field because it is seeing low voltage (blue wire connection on the regulator)
The regulator is causing it to full field because it has failed internally.
Click to expand...
10-4 will be back at it later today. Thanks again…Swingn’
 
Mattax said:
The problem in this case is maximum current flowing though the rotor, aka full fielding.
You jumped ahead by not first determining if there is a ground problem in the field circuit. Perhaps not clearly stated, this would have been by checking for grounding with the field wires still connected to the alternator.


Regardless, you've now narrowed it to three possibilites:
The green wire is connecting to ground somewhere.
The regulator is causing it to full field because it is seeing low voltage (blue wire connection on the regulator)
The regulator is causing it to full field because it has failed internally.
Click to expand...
Checking voltage at the battery, starter relay post, alt post, blue field wire, ballast high side, and VR blue wire are all very close. Key on and everything connected. BUT by accident I checked the green field wire at the alt and was picking up 2.4 volts also. Regulator-1 regulator-2 it was 1.5 volts and regulator 3 it was .09 volts..?? Regulator 3 regulates at 14.8 at full steam. Are the other 2 faulty or n.g. Inside..?? Looks a though the alt is acting as it should..?? Thanks again Swingn’…!!
 
Mattax said:
The problem in this case is maximum current flowing though the rotor, aka full fielding.
You jumped ahead by not first determining if there is a ground problem in the field circuit. Perhaps not clearly stated, this would have been by checking for grounding with the field wires still connected to the alternator.


Regardless, you've now narrowed it to three possibilites:
The green wire is connecting to ground somewhere.
The regulator is causing it to full field because it is seeing low voltage (blue wire connection on the regulator)
The regulator is causing it to full field because it has failed internally.
Click to expand...
Mattax said:
The problem in this case is maximum current flowing though the rotor, aka full fielding.
You jumped ahead by not first determining if there is a ground problem in the field circuit. Perhaps not clearly stated, this would have been by checking for grounding with the field wires still connected to the alternator.


Regardless, you've now narrowed it to three possibilites:
The green wire is connecting to ground somewhere.
The regulator is causing it to full field because it is seeing low voltage (blue wire connection on the regulator)
The regulator is causing it to full field because it has failed internally.
Click to expand...
Checking voltage at the battery,starter relay post,blue field wire,ballast high side,and blue wire at the VR are all very close. But by accident I checked the green wire at the alt and was getting 2.4 volts..?? Regulator -1 regulator -2 1.5 volts and regulator-3…. .09 volts..reg-3 charges at 14.8 at full steam. Are the other 2 bad or faulty inside ..?? The alternator appears to operating as it should..Thanks…!! Swingn’
 
The green wire is the control wire, and the VR for a simple explanation, controls "the amount of ground" The VR controls the amount of current through the field to regulate the output voltage. The amount of current through the field causes a stronger magnetic field, and that causes more output from the alternator.

the voltage you measure on the green really does not tell you anything. I'd say you have a intermittent bad connection somewhere. "Wiggle" connections and wiring and especially the bulkhead connector.

This could be a bad regulator OR A POOR GROUND at the regulator
 
67Dart273 said:
The green wire is the control wire, and the VR for a simple explanation, controls "the amount of ground" The VR controls the amount of current through the field to regulate the output voltage. The amount of current through the field causes a stronger magnetic field, and that causes more output from the alternator.

the voltage you measure on the green really does not tell you anything. I'd say you have a intermittent bad connection somewhere. "Wiggle" connections and wiring and especially the bulkhead connector.

This could be a bad regulator OR A POOR GROUND at the regulator
Click to expand...
Probably defeated the VR ground at this point. Not much car left that couldn’t be grounded. All of what it came with and extras as well. Possible intermittent connection more likely. More wiggle and connection tests to do. At least I’m’ not in the 18 volt range now..!! Thanks for all the help..!! Swingn’
 
Swingn’71 said:
Checking voltage at the battery, starter relay post, alt post, blue field wire, ballast high side, and VR blue wire are all very close. Key on and everything connected. BUT by accident I checked the green field wire at the alt and was picking up 2.4 volts also. Regulator-1 regulator-2 it was 1.5 volts and regulator 3 it was .09 volts..?? Regulator 3 regulates at 14.8 at full steam. Are the other 2 faulty or n.g. Inside..?? Looks a though the alt is acting as it should..?? Thanks again Swingn’…!!
Click to expand...
I don't know why you are measuring voltage? I don't know what 'close' means. It sounds like you're swapping regulators? That's a method of troubleshooting but not the one I was suggesting.
 
Mattax said:
I don't know why you are measuring voltage? I don't know what 'close' means. It sounds like you're swapping regulators? That's a method of troubleshooting but not the one I was suggesting.
Click to expand...
10-4 I understand, only reason I swapped regulators was to see if any one would show a major difference to the others. The reason for voltage checks was to see if there were any drops big enough to create a charge voltage that high. When I say close 12.8 compared to 12.7 or 12.6 on the other components. Still not sure why there would be ANY voltage at the green wire..
 
Swingn’71 said:
10-4 I understand, only reason I swapped regulators was to see if any one would show a major difference to the others. The reason for voltage checks was to see if there were any drops big enough to create a charge voltage that high. When I say close 12.8 compared to 12.7 or 12.6 on the other components. Still not sure why there would be ANY voltage at the green wire..
Click to expand...
Because there is some small amount of resistance to the current flowing between the point you are measuring and ground.
 
Why not finish testing for shorts to ground?
That narrows the issue down real fast.

The two tests 1WildRT do a similar thing, but since you have a multimeter, why finish testing for shorts to ground.
 
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Mattax said:
Key off. Take a multimeter set on resistance or continuity. Put one probe on the alternator housing and backprobe each brush terminal.
If they connect with ground, then its in the alternator or the wiring. Disconnect each field wire from the brush terminals. Check each until you find the one that's grounding.
Click to expand...
You checked for a ground short in the field circuit of the alternator itself.
But you haven't checked the field circuit from the alternator through the voltage regulator for a ground short.
Do that.
Only if its not shorted, does it become a matter of deciding whether its a matter of the regulator or wiring to the regulator.

1. The green wire is connecting to ground somewhere.
2. The regulator is causing it to full field because it is seeing low voltage (blue wire connection on the regulator)
3. The regulator is causing it to full field because it has failed internally.
 
We ACTUALLY had one member here who had somehow got the green wire pinched between the valve cover and block, and it was shorting.
 
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