Installed new electronic volt regulator and....

[440beep]

a new Powermaster 75amp alternator, and the car starts and runs fine, HOWEVER, the amp meter in the dash nows responds with the idle. When the car is idling the dash gauge needle jumps around the middle with the idle; and when I rev the engine the gauge needle shoots to the right with the increased revs. Is something wrong?

 

[67 coronet]

not really.solid state voltage reg react faster then mechanical ones,plus you went to a higher amp alt then stock wich will cause more fluctuation as well.does you motor have a good ground to the body of the car?bad eng ground can cause pulsations in the electrical system.

 

[Bee383]

put a voltmeter at batt terminals and see what you get at idle and at higher rpms.if you are getting
over 15-16 volts you are overcharging the battery.if the new regulator is working you should'nt see much over 14 at battery

 

[bigmanjbmopar]

Modern alt needs modern regulator. Stock amp is 35 I think and now you replaced it with 75. quite the jump I would upgrade the rest of the system and use voltmeter instead unless you are worried about the stock appearance. If so you might want to consider upgrading the wires that go to the amp meter remember more current = more heat smaller wire = more resistance = problems increase the gauge of the wire by 2 and you should see a difference. Also increase the wire from battery to alternator.

 

[440beep]

Well, bad news. At idle, the battery voltage is 17v, and at 2k RPM the battery volts is over 18v. So WTF?! Does this mean I hooked up the Mopar electronic voltage wrong, or the 75amp alternator is too much?

If I wanted to keep the electronic voltage regulator installed and go back to my small alternator, how would I hook up the single phase alternator?

Oh, and the Powermaster alternator I'm using is #7018, which is stated to be a 50amp alt.

 

[67 coronet]

are you sure you have not jumped the regulator with wiring in some way?thar is some monster voltage at the battery.have you done any wire mods with the new alt and reg?

 

[bm02tj]

look to see what voltage the regulator is seeing that is what it is trying to get to 14 volts then make sure it is seeing battery voltage

alt size has nothing to do with the voltage

 

[440beep]

I'm following the instructions at the end of this article, #20. I think it might be a bad ground, because as I improve the ground the battery voltage is decreasing.

http://www.allpar.com/history/mopar/electrical.html

 

[67 coronet]

good grounds are the key to good electrical.many people are afraid to grind on nice paint,but many times it is a must.

 

[440beep]

No, wasn't a ground issue, still seeing 16v+.

 

[A383Wing]

something is either wired wrong or regulator is bad....pic below of how it should be wired

Bryan

 

[440beep]

that's how I have it hooked up. Green wire straight from regulater to alternator. I have the blue wire out of the regulator going to the alternator and into this blue wire I have two other wires spliced into it: 1 blue wire from the ballast resisitor and a blue wire w/white trace on it (the two wires that were previously connected to the ignition side of the old mechanical regulator). I'm so at a loss with this.

But here's an issue, I'm only getting 9.5v in/out of the 4 prong ballast resistor and also 9.5v out of the electronic regulator. WTF?!

 

[snakeoil24]

Make sure you have a good ground for regulator. Is this car originally a single field alternator? or later 2 wire? it should not matter if it is a 35 amp or 75 amp alternator. The regulator is not controlling the fields in the alternator. You have to check your wiring line by line. If you are sure then regulator like A383wing is bad.

 

[440beep]

I got the car with a single field alternator.

And it has a good ground, its grounded right to the firewall engine ground.

 

[bm02tj]

if you have bad voltage to the reg you will have wrong out put for alt
put you volt meter on reg input

 

[440beep]

So with the car off, the batt voltage at the alternator is 12.45. With the key in the "on" position, the batt volts at the altnerator drops to 10.40v(?).

 

[snakeoil24]

short some oplace or a ground issue still.

 

[A383Wing]

wait a minute...are you still running single field alternator with dual field regulator?

 

[440beep]

NO. Its a dual field alternator. PM#7018.

What's the f'ing chance the brand new MP voltage regulator is defective?

wait a minute...are you still running single field alternator with dual field regulator?

 

[A383Wing]

actually, I have seen regulators out of the box that are bad...sounds like alternator is being full fielded by regulator...or maybe alt is shorted inside....unplug regulator and start engine...is it still over charging now?

Bryan