Voltage regulator question

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darepairman

darepairman

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Hey fellas, I have a 72 Dart with a 318, I installed a kit from Summit with a Mallory 6A ignition box, comp SS 32 series distributer and Mallory coil. I removed the old ignition box and ballast resister and used the wire from the regulator to the old resistor for the switched power supply, when I fired it up it started up and ran and then the RPM went way up so I turned it off, come to find out the 6A fried, exchanged it for a new one. but before I hook it up I am making some checks, Bought a new regulator, now checking the voltage on the switched wire I put it on a charger and I read 16 volts when on a charger after the regulator, My question is, is this normal to read high voltage after the regulator? I dont know if this fried the 1st unit cause I was using the charger to start it.
Thanks Ed
 
Well it's possible. 16 Volts is getting a bit high. The OTHER thing is, GOOD batteries, which are PROPERLY hooked up with adequate, clean cables provide what could be called a "low impedance."

What this means is that any spikes or "dirty power" will normally be absorbed by the battery, which is trying to "suck in" that dirt like a big black hole.

But a battery that is fully charged, maybe OVER charged, and / or a battery which is getting a little bit "lame" in power output won't do that.

So you put the Great Big charger / booster on there and what? You have too much voltage and it's DIRTY voltage, not filtered, spikey. If you were to turn on the AM radio, you would hear HUM. LOTS of HUM. This is coming from the dirty charger

So yeah. it could have caused the failure.
 
Thanks for the reply, The battery is good just down on charge from sitting, all the connections are good and clean its a rebuild job from the rotissory on up and all connections were cleaned, my big question I guess is shouldnt the regulator drop the voltage down to 12 volts?
Thanks Ed
 
Regulators regulate the alternator output by controlling the field. It has nothing to do with regulating your battery charger.
 
I understand it doesnt regulate my battery charger, I am just asking if it regulates voltage after the battery regaurdless of the voltage input from the battery say i am putting 16 volts in at the battery does the reg. drop it down to 12 or not sounds like from your explination the answer is no
 
The regulator regulates the voltage output from the alternator, which feeds the battery and the whole system. It will not do anything to regulate/drop voltage from any device external to the alternator; it wil not regulate battery voltage.

Any time you connect a charger to the system, the components in the system will have to withstand the higher voltage that the charger puts out to drive charge into the battery. 16v and higher voltage spikes from a caharger are quite common; some chargers are better than others for begin 'clean'. And some add-on electronics will be more easily damged by over-voltage than others.

Don't ever use a charger in place of your battery to run the car. The battery serves a function caused 'ballast' on the car's electrical system that the regulator depends upon to keep voltages well regulated; a charger does not provide this 'ballast' function at all. Even not running, using a charger to run the electrical system is bad becasue of the dirty nature of the voltage output of pretty much all chargers. Only a good, clean well regulated power supply with adequate amperage should be used to run a car's system and that ONLY in a non-running mode.... and only maybe 1 out of a 1000 car guys will have this.
 
Thanks and no I wasnt using the charger inplace of the battery, I have never even thought of that. But my question was answered
Thanks again Ed
 
darepairman said:
does the reg. drop it down to 12 or not sounds like from your explination the answer is no
Click to expand...

No.

the battery when the engine is stopped will vary depending on it's charge level. "Fully charged" lead acid is about 12.6. This also depends on temperature.

A "running" that is properly running system, properly regulating and charging, going 'down the road' regulates the system voltage at 13.8, plus or minus a bit. Optimumally, this should run about 13.8--14.2 with engine and battery warmed up and "normalized."

On the outside, no less than 13.5 no more than about 14.5

This is caused by the regulator controlling the alternator
 
I use a cigarette lighter voltmeter in all my cars. Harbor Freight has a real cheap LED one that works OK. In most, 12.6 V off and ~14.2 V running. Not an electro-chemist, but I expect it takes ~1.6 V above battery voltage to cause current to flow into the battery.

For those who see excessive voltage with the engine running (not O.P.), Vreg regulates to the voltage drop it sees, which is from its case to the IGN1 wire at it (blue). It tries to hold that drop at ~14 V by increasing or decreasing the alternator output current. Measure that drop with a multimeter to see if Vreg is doing its job. If so, and you measure say 16 V elsewhere (BATT- to ACC), find where the excess drops occur - bulkhead connector, Vreg case to BATT-, key switch, ...
 
I am using this blue wire that was on the ballast resistor to fire the Mallory 6a box when the box fried, could this be a problem? I used it because it was switched. (the ballast resistor has a been taken out and the remaining wires caped off)
Thanks Ed
 
darepairman said:
I am using this blue wire that was on the ballast resistor to fire the Mallory 6a box when the box fried, could this be a problem? I used it because it was switched. (the ballast resistor has a been taken out and the remaining wires caped off)
Thanks Ed
Click to expand...

I've lost track of your problem, could you re--define it?

MSD has to have "main" battery power and ground hooked to the "big red" and "big black." ---That is---hooked to the starter relay battery stud, example. The "small red" is just like a relay trigger wire, and that is what should be hooked to your dark blue "ignition run." Also, the brown bypass / IGN2 needs to be jumpered to the blue

If you UNHOOKED other loads hooked to the blue, the thing won't charge, as the blue branches off to feed the regulator, and depending on car model year, "other stuff."

A HUGE PROBLEM with these cars is voltage drop in that dark blue circuit. This is always the same causes...........the red and dark blue terminals in the bulkhead connector, ammeter connections, connections at the ignition switch and IN the switch itself, and in rare cases, failure of the "in harness splice."

ANY drop in this circuit ADDS to the charging voltage.

ABOUT YOUR original question........IF you are going around measuring voltages in the car WITH a battery charger hooked up then NONE of those measurements mean a thing.
 
67Dart273 said:
ABOUT YOUR original question........IF you are going around measuring voltages in the car WITH a battery charger hooked up then NONE of those measurements mean a thing.
Click to expand...
I was re-reading the original post and came to the conclusion that the OP was measuring the 16V at the VR/ballast connection WITH the charger connected; in that case, the above comment from 67Dart273 is valid: you don't know what extra spikes the carger is putting on the system, and how the voltmeter will react to it. (Especially a cheaper type).
 
All right I guess I have lost the true problem I am having, The battery charger was just a test I ran because I had the charger on it to start it originally when I lost the Mallory box.
Now here is the thing, I have the box hooked up like this,,The heavy red wire to the battery terminal and the heavy black to chassis ground, I am using the blue wire from the ballast resister to trigger the small red wire. the rest of the wires are caped off from the BR, I will re connect them as one poster suggested for charging pourposes. Now the purple and green wires are on the Mallory comp ss distributer and the small black and orange are going to the Mallory coil. Now I lost the 1st ignition box when the car started and gained rpm soon after start up and I shut it down,checked the carb settings. then it woldnt start and I lost all spark, checked the box and no led light sent it back for a new one, thats when I checked all voltage and tried to duplicate the condition with the charger and with out before I changed the box, being satisfied that everything was good I installed the new box and guess what?? no spark and no led light in the box, now I am really at a loss as to what could be going wrong because everything still has power the way it should. Does this help? oh and no charger with the second box.
Thanks Ed
 
Assmuing you haave a stock ignition switch and wiring: Do you have the brown wire from the bulkhead connector that goes to the ballast resistor also tied to the blue wire, with both going to the small red wire on the 6A? That is needed to have activation voltage for the 6A when cranking; the blue wire will only have +12V on it when the key is in RUN, but not when the key is in START. The brown wire will provide +12V to the unit when the key is in START.

Let's do a basic test: Turn on the key to RUN but not to START, and see if you get the LED to flash as per the instructions (set up a mirror if you need to see the LED while at the key); this wiil give an indication that the unit is getting approx +12V to the small red control lead on the blue wire. Let us know if this works as a basic test of power.

HYFIRE​
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® 6A Diagnostic LED​

On the end panel of your Hyfire 6A ignition there is a small hole. Behind this hole is a red LED indicator. This serves two purposes: when you first turn on the ignition switch, the LED will flash
rapidly 3 times. This indicates that the ignition system has power, and that the microprocessor is running properly. In addition, the LED will flash when receiving a proper trigger signal from the vehicle. If, after a normal power-up, the LED doesn’t flash when cranking the engine, you should check your triggering circuit for problems. If the LED flashes when the engine is cranked, but there is still no spark, the problem lies somewhere else.​
 
nm9stheham said:
Assmuing you haave a stock ignition switch and wiring: Do you have the brown wire from the bulkhead connector that goes to the ballast resistor also tied to the blue wire, with both going to the small red wire on the 6A?
Click to expand...

THIS

You have TWO power wires coming from the ign switch through the bulkhead

The blue, "run" or "IGN 1" goes dead in start

The brown, "bypass" or "IGN 2" is the only power available during cranking for ignition power

For all I know that might have been "what was wrong" with the first box
 
^^^ In which case, I am trying to figure out how the car started in the first place.... maybe the engine was still spinning and the key was released and the 6A finally got juice at that instant. Hopefuly, it is this simple.
 
Ya it dosent make sence that the car started, well I will try this when I get home from work, you guys have been a great help for me to understand this whole deal, Ill get back to ya
Thanks Ed
 
Wait a minute,,, when the car started I had the ignition in run and turned it over with a remote switch, and this is also how I checked for spark and had none or a lit LED
 
Well the remote switch WOULD allow the 6A to work with the ign sw in RUN. That part now makes sense.

But check it all out again please, and reference the instructions quoted above: see if the LED flashes the moment right after the key is turned to RUN; you need to have someone turn the key while you watch or use the mirror thing to see the LED the moent your turn on the key to RUN. If this LED flashes 3 times the moment that the key is turned on, then we know the 6A is not bad.

Then if that is good, then the issue probably is in the distributor pickup or wiring. Then we can move on and fix the wiring so it works in START and in RUN. Just trying to make this orderly so we can help you figure it out 'via remote control' so to speak! That helps us since we can't be there in person. (Drinking your beer, etc....LOL.)
 
OK here we go, I fixed the ignition wire problems with the brown and blue, and checked the box, its good. I get tunnelvision sometimes, but I tried it and no spark, so tomorrow I will hook up another coil to see if its that. maybe the coil took out the first box? but this great help but I wouldn't want you here, I really don't like people who might drink my beer, nothing personal.
Thanks Ed
 
OK, let us know.... You can do one more test..... Put the key in RUN, and use your remote start switch to crank the engine. Watch the LED....it ought to be blinking, or on in some fashion, while cranking IF the distributor is providing good trigger pulses to the 6A box.

I guess it is BYOB when I show up at your place.....
 
Ill do that tonight, as for the beer, I am a machine repairman at Miller/Coors in Milwaukee, so beer is never a problem. :thumblef::thumblef:
 
Get rid of the ballast resistor and connect the brown wire and the blue wire that come from the ignition switch to the small red wire of the MSD. I just went through this on my '69 Dart and it starts & runs great.
 
darepairman said:
Ill do that tonight, as for the beer, I am a machine repairman at Miller/Coors in Milwaukee, so beer is never a problem. :thumblef::thumblef:
Click to expand...
Ah Miller Valley, eh? I'd guess your only beer problem coudl be 'too much of a good thing'!:)
 
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