I replaced my alternator and my external regulator on my 77 but im still getting 19 volts.?

Question

I own a 1977 dodge b200 van with a 5.2 (318) motor and a double barrel carb. My old voltage regulator went out so i replaced my alternator and my regulator. I took care of grounding my new voltage regulator and i made new conections to my alternator. My batery was reading 18 volts so i got it tested and my regulator tested bad. I cleaned my connections again and replaced my regulator with a more expensive brand. Didnt fix my problem. My van is still reading 18+ volts while running. What do i do?

Answer 1

Having had EXTREME electrical experience in the last almost half century, the first thing I would check is your voltmeter!! At 18 or 19 volts your battery should be BOILING! And the alternator would probably be putting out it's maximum.



So get an accurate voltmeter, first of all. Verify the facts!



p s. Does your alternator have 2 single terminal connectors (on thin wires) that connect the wiring harness to the alternator? It's called an isolated field alternator. If yes, then switch those 2 connectors, and make sure your regulator works. If it wont charge, get a new regulator. I'm not talking about the heavy wire that is attached to the alternator output stud with a nut.

Answer 2

The ballast resistor is for the coil. Nothing else. Alternators can put out high voltage up to over 20 volts. Voltage regulators do control voltage that's why they were invented because generators would increase voltage as the engine increased rpm's up to 32 volts. Another thing everyone seems to miss is that a battery can cause high voltage. Amperage decreases, voltage rises. A good alternator should show over 14 volts at the battery. I have tested batteries with the car shut off that showed 15 volts with a new Snap on Tester.

Answer 3

The regulator doesn't reduce voltage. It simply keeps the voltage constant. A bad regulator will cause voltage pulses. This is commonly noticed by lights constantly getting brighter and dimmer. Kind of like in your house if you have a dimmer switch and someone is turning it up and down and back again repeatedly.





I would venture a guess and say the gauge is inaccurate. Have you bothered to test the output voltage with a legitimate meter?







Edit for JJ: "The voltage regulator can be mounted inside or outside of the alternator housing. If the regulator is mounted outside (common on some Ford products) there will be a wiring harness connecting it to the alternator.



The voltage regulator controls the field current applied to the spinning rotor inside the alternator. When there is no current applied to the field, there is no voltage produced from the alternator. When voltage drops below 13.5 volts, the regulator will apply current to the field and the alternator will start charging. When the voltage exceeds 14.5 volts, the regulator will stop supplying voltage to the field and the alternator will stop charging. This is how voltage output from the alternator is regulated. Amperage or current is regulated by the state of charge of the battery. When the battery is weak, the electromotive force (voltage) is not strong enough to hold back the current from the alternator trying to recharge the battery. As the battery reaches a state of full charge, the electromotive force becomes strong enough to oppose the current flow from the alternator, the amperage output from the alternator will drop to close to zero, while the voltage will remain at 13.5 to 14.5. When more electrical power is used, the electromotive force will reduce and alternator amperage will increase. It is extremely important that when alternator efficiency is checked, both voltage and amperage outputs are checked. Each alternator has a rated amperage output depending on the electrical requirements of the vehicle."

Answer 4

19 volts will boil the battery. My suspicion is that your tester may be faulty. Try another one.



History: I was helping a friend trace out a constant drain on his battery when my meter started reading higher and higher voltages. The engine was NOT running, so there was no source for the higher voltages. So I grabbed a different meter and found the voltages were where they were supposed to be.



Wondering why my other meter was acting out I checked the battery. Turned out the battery in that meter was dying. You may have a bad battery in your tester. If you don't have an alternative meter then try replacing the battery in that one. It's possible you're wasting money on your car when you don't need to.

Answer 5

must be stinkin up the van.

Oozin battery juice. Gassing off hydrogen gas.

and ready to go pow.

16v would be hard to be in the same room with sitting on a charger.

You can taste it in your fillings.

Digital voltmeters and multimeters that are made in Oregon by JL Fluke

are the base starting point for an actual journeyman technician.

When you use other types of cheap stuff,

You have to compare often to known good.

You have your vehicle wired the same as mopar had it?

You use real parts?

If your DVOM is still out of spec with the reading after trying

a meter that reads normally for a second vehicle?

If your reg is still outta whack, put the old one back on

A known good OEM part from pik n pull could solve it.

But study the schematic. read a motor or chilton for your design at the library. some info can be sought with a library card online for free.

or at the database station on site.

When you understand your vehicle, and how it was wired or may now be or what tests to run and their connections, then you could say what you did to it, or if it was allright the whole time.



It sounds so unusual and far fetched, you best question EVERYTHING.

study the tech's manual and learn all about your vintage.

They could even let you take it a few days or photocopy for loose change.

My experience with dropping resistors is for systems wired differently, I would have to study yours.

I googled, chrysler charge system schematic 77 b200

You can read about every attempt and how to save it, that mopar ever made.

Systems evolved as time passed and all the while that reet zistor was just like a car uses in a resistor wire shielded in the harness, yours was just a great big ugly unit that was affixed in the fresh airstream connected with primary wire. So its like a normal vehicle, except alt field+ goes to reg and alt field - goes to GND. you will see the many choices for schematics, pick the one that's like yours. simple.

A ballast resistor drops supply voltage to the ignition to run cooler after starting.

Your regulators connections for testing, readings and everything they say they made, as well as how to correct and improve it is all there.

The cops used them for years, but they had their own repair shop and the public's funding.

Excuse my attitude, I just feel creepy when I see their stuff.

Answer 6

I know why he is anonymous, because he doesn't know what a "voltage" regulator does.

With voltage that high you would cook the battery to a point it would get hot and you would be blowing light bulbs often. So the first thing I'd have to question is if you multimeter is correct. You can use a flashlight battery to test that. If that is correct then I'd be looking at the wiring. Go online and get a diagram and check to see if your wires go to the right place. I don't think you could have gotten two bad regulators.

Answer 7

What are you using for voltage testing. Alternators don't produce voltage that high, the windings won't allow it. If you do have a true 18V, there is a problem with that alternator.

Answer 8

Not sue if it is possible to go that high, make sure your meter is correct by checking a different car.



This shows how your system is wired.

http://moparforums.com/forums/f84/5-2-318-alternator-13752/

Answer 9

Does this van still use ballast resistors? If so, try replacing that.