over charging regulator issue

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Vitamin c

Vitamin c

Vitamin c
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Having an issue with an over charging alternator. Seems to be putting out full power continuously. Last night at the strip it cooked the voltage regulator. I have tried both points and electronic regulators and finally cooked the points style last night. Im not sure if this could be a grounding problem or what. recently on another post i read some ohm resistance numbers, anyone have those handy? ( i did check the grounds today and everything seemed ok. car starts/runs fine, but amp meter is over in full charge. alternator is putting out 15 volts and the field wire has 12 volts at idle. as you raise rpm the field wire volts dont change much. i checked a friends car and his alternator was also putting out 15 volts but his field wire was down around 9 and seemed to change with rpm.
 
Hey, saw your final post on the alternator belt issue, glad that is fixed. We must living in parallel car universes because I just fixed my regulator problem. Do your headlights vary with your engine speed? If yes, then it is definitely your regulator. Make sure your regulator has a good ground. I ran a separate ground wire from a known good ground point on the firewall to the regulator, do NOT rely on regulator mounting bolts for ground! An ohmmeter is your friend when checking grounds. Make sure all connections are clean and tight.
 
By the way, a good electronic regulator should have about 275 to 300 ohms between the regulator case and one of the two connection pins on the regulator when disconnected. You should show an "open" between the two pins and an open between the other pin and ground. Sorry I can't remember which pin shows the resistance to ground.
 
Demon 408 said:
By the way, a good electronic regulator should have about 275 to 300 ohms between the regulator case and one of the two connection pins on the regulator when disconnected. You should show an "open" between the two pins and an open between the other pin and ground. Sorry I can't remember which pin shows the resistance to ground.
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well i havent run the car at night to check the head lights,but ill check. this issue starting with the very first run of the motor. ill also check the pins to ground
 
FYI i am running a trunk mount battery, electric fuel pump with relay, electric fan with relay, msd ignition, new year one engine wiring harness, new power master alternator, and a painless alternator cut off relay.
 
Like I said, good grounding of all components will help, especially the voltage regulator. My battery is in the trunk also. I grounded back of motor to wiper motor stud using a braided ground and grounded front of motor to driver side framerail using battery cable (clean off all paint). I grounded negative battery lead to brace in trunk that is welded to rear frame section.

See my thread on electrical upgrades I did for my Demon: http://www.forabodiesonly.com/mopar/showthread.php?t=73437
 
Demon 408 said:
Are you using a stock style electronic regulator, (bolts to the firewall next to the master cylinder)?
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yes, ive tried both, i actually started with the electronic and thought i had a problem, then switched to the points style. after checking a friends car for comparison, i decided to run mine thinking maybe i was just imagining a problem. last night the points style quit, so im back to the electronic.
 
Like Demon said, drill a hole in the kframe, then run regular battery cable from there to the head, driver side. Fixed my mess. Batt in trunk, engine is using all its small grounds. Neg was bolted on head when the batt was up front.....Then retry.
 
You said the field wire was showing 12volts. That sounds like the regulator thinks the battery is low, and the alt needs to charge it.

With the car turned on (but not running) what is the voltage on the other wire that goes into the VR? It should be pretty much the same as the voltage at the battery. If it is lower than the battery voltage, then you need to trace that wire back, checking voltage to see where the drop is.

Not sure how your race car is wired, but the factory setup sent that power from the + battery terminal to the starter relay, then through the bulkhead connection to the main splice. (That's a bunch of wires connected inside the main harness under the dash) From there one wire went to the ignition switch, and with the switch on, the power goes through another wire from the switch, back through the bulkhead connection to the VR.
 
D Cluley said:
You said the field wire was showing 12volts. That sounds like the regulator thinks the battery is low, and the alt needs to charge it.

With the car turned on (but not running) what is the voltage on the other wire that goes into the VR? It should be pretty much the same as the voltage at the battery. If it is lower than the battery voltage, then you need to trace that wire back, checking voltage to see where the drop is.

Not sure how your race car is wired, but the factory setup sent that power from the + battery terminal to the starter relay, then through the bulkhead connection to the main splice. (That's a bunch of wires connected inside the main harness under the dash) From there one wire went to the ignition switch, and with the switch on, the power goes through another wire from the switch, back through the bulkhead connection to the VR.
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That seems to be the issue, the field wire 12V is telling the alternator to keep charging. comparing it to a 67 dart charging system, it only showed 9ish volts to the alt field. Today ill check the what you have described with the ignition switch and etc. Other posts have described problems with the ignition switch, amp guage, or bulkhead connector. Im running the origional (old untouched) ignition switch, dash harness, but (new) engine harness, battery cables, alternator, regulator,ignition. Also the guage cluster has been restored by Just Dash's
 
I would agree that the voltage regulator is not seeing the 15v. that you say is being put out by the alternator and so the regulator is telling the alternator to keep fully charging. You need to see what the imput voltage is going into the voltage regulator from the ign. switch measured @ the regulator????

And also make sure the regulator has a very good ground!
 
Vitamin c said:
... Other posts have described problems with the ignition switch, amp guage, or bulkhead connector...
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That totally makes sense. Each of those is in the path that leads to the voltage regulator, so a problem with any of them, would mean less voltage at the regulator.
 
nothingbutdarts said:
I would agree that the voltage regulator is not seeing the 15v. that you say is being put out by the alternator and so the regulator is telling the alternator to keep fully charging. You need to see what the imput voltage is going into the voltage regulator from the ign. switch measured @ the regulator????

And also make sure the regulator has a very good ground!
Click to expand...
im heading to the garage again today, IIRC the voltage to the bottom of the regulator is in the 12.5 range, with around the same heading to the alt. It appeared to me after checking a friends 67 that that his voltage coming out of the reg. to the alt was in the 9 range. Does the less voltage to the alt field wire make the alt. put out less power? im at 12+ heading to the alt. field.
 
nothingbutdarts said:
I would agree that the voltage regulator is not seeing the 15v. that you say is being put out by the alternator and so the regulator is telling the alternator to keep fully charging. You need to see what the imput voltage is going into the voltage regulator from the ign. switch measured @ the regulator????

And also make sure the regulator has a very good ground!
Click to expand...
ya, ive got a problem somewhere, its just knowing what your looking at with the voltmeter. ive started checking ohms resistance on a few connections. What is a good, and or bad reading in ohms resistance?
 
Just thought of something worth mentioning. the power master alternator i have came as a 70up duel field unit that i switched to a single field unit by swapping the ground tab from an older alternator i have. Not a real complicated switch, but could there be a problem there?
 
Vitamin c said:
Just thought of something worth mentioning. the power master alternator i have came as a 70up duel field unit that i switched to a single field unit by swapping the ground tab from an older alternator i have. Not a real complicated switch, but could there be a problem there?
Click to expand...

Yes, if you have your voltage regulator connected for a dual field alternator. Read this: http://www.allpar.com/history/mopar/electrical.html
 
My ($50.00 replacement cost) Regulator fried my $350.00 stereo in my '71 Dart.
Was a quick lesson in the importance of checking electrical system parts when things aren't going just right. I had the same headlight strength fluctaution with engine speed and wound up replacing the alternator, then the regulator and finally the stereo.
Ever feel as though there's a Global Conspiracy afoot designed to separate you from every dollar you have?
 
Vitamin c said:
Just thought of something worth mentioning. the power master alternator i have came as a 70up duel field unit that i switched to a single field unit by swapping the ground tab from an older alternator i have. Not a real complicated switch, but could there be a problem there?
Click to expand...

You have to wire the two field alternator as shown in the drawing provided with the link in deamon408's posting from "allpar" which is a very great article. the second field that I believe you have run straight to grouind needs to be run back to the regulator. In other words, the blue wire going into the "electronic" regulator gets it's power when you turn on the ign. key. It will have battery or charging voltage! this same blue wire is also hooked to one field terminalwhick will put battery/charging voltage to the one field terminal. The second field terminal goes back to the other wire in the regulator. It is this wire that is doing the "output regulation" of the alternator! Does this help?
 
nothingbutdarts said:
You have to wire the two field alternator as shown in the drawing provided with the link in deamon408's posting from "allpar" which is a very great article. the second field that I believe you have run straight to grouind needs to be run back to the regulator. In other words, the blue wire going into the "electronic" regulator gets it's power when you turn on the ign. key. It will have battery or charging voltage! this same blue wire is also hooked to one field terminalwhick will put battery/charging voltage to the one field terminal. The second field terminal goes back to the other wire in the regulator. It is this wire that is doing the "output regulation" of the alternator! Does this help?
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I am running a single field wiring harness and voltage regulator. The alternator was purchased as a duel fiield unit when i was heading a different direction with ignition components. Mid stream i decided to go back to a single field alternator, (i know, i know) so i pulled the grounding post from an old alternator i had laying around and put it on the duel field power master alt. My thought was, did i miss somthing in changing the alt. from a duel to single field? I have finally dug out the service manual and will start testing this week when i get some help from a friend.
 
Vitamin c said:
I am running a single field wiring harness and voltage regulator. The alternator was purchased as a duel fiield unit when i was heading a different direction with ignition components. Mid stream i decided to go back to a single field alternator, (i know, i know) so i pulled the grounding post from an old alternator i had laying around and put it on the duel field power master alt. My thought was, did i miss somthing in changing the alt. from a duel to single field? I have finally dug out the service manual and will start testing this week when i get some help from a friend.
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OK, so you said you ran an electronic regulator and it did the same thing. What type of electronic regulator was it you tried???

And yes, I have used a dual field alternator in a single field syst. and have just put the second field terminal to ground as you said you did.
 
1. Yes, the amount of voltage going through the field wiring is what controls the output of the alternator (along with how fast it is spinning)

2. Depending on which type of regulator you are using they are hooked up differently.

The older style regulator was designed for single field connection. This is the cube shaped box with two separate wire connections. The original versions is basically a relay with points that open and close. There are now electronic versions, but they look the same and get hooked up the same.
The green wire from the regulator goes to the field connection, and provides the + voltage.
The other field connection is the ground and is the tab that goes to the alt case.
If you are using a newer 2 field connection alt, you can either replace that tab to ground to the case, or add a separate ground wire.

The newer style regulator is designed for the dual field connection alts. This is the flat box with the triangular plug with both wires.

These have to be wired up the opposite way! There is an extra blue wire that provides constant + voltage, and the green wire is controlling the ground connection.
 
nothingbutdarts said:
OK, so you said you ran an electronic regulator and it did the same thing. What type of electronic regulator was it you tried???

And yes, I have used a dual field alternator in a single field syst. and have just put the second field terminal to ground as you said you did.
Click to expand...
the electronic regulator im using looks just like the origional points style, but with electronic internals. i think i got it from year one.
 
D Cluley said:
1. Yes, the amount of voltage going through the field wiring is what controls the output of the alternator (along with how fast it is spinning)

2. Depending on which type of regulator you are using they are hooked up differently.

The older style regulator was designed for single field connection. This is the cube shaped box with two separate wire connections. The original versions is basically a relay with points that open and close. There are now electronic versions, but they look the same and get hooked up the same.
The green wire from the regulator goes to the field connection, and provides the + voltage.
The other field connection is the ground and is the tab that goes to the alt case.
If you are using a newer 2 field connection alt, you can either replace that tab to ground to the case, or add a separate ground wire.

The newer style regulator is designed for the dual field connection alts. This is the flat box with the triangular plug with both wires.

These have to be wired up the opposite way! There is an extra blue wire that provides constant + voltage, and the green wire is controlling the ground connection.
Click to expand...
the green field wire is putting around 12 volts to the alternator which i think is telling the alternatore to make more power. The service manual has a couple resistance test that i need to work on this week. i must have a bad connection at the key switch or under the dash somewhere. from what i can see the bulk head connector seems ok.
 
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