Battery not charging

Measure alt. Voltage at battery terminals with voltmeter with engine running, should have 13.5-14-5V.

If good, then you may have a drain in electrical system.

Is alt. Original or a replacement?

The Alt. Is bad.

It sounds like you have a bad connection at the alternator or a blown fusible link. Here is a guide and a alternator wiring diagram so you can do a simple test to see where you lose power. Check the meter fuse.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

and

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

and

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Check out the diagrams (Below)

Please let us know what you find. We are interested to see what it is.

Cheers, Ken

You have to test the generator while the problem is occurring. Use an inexpensive digital voltmeter to measure the battery voltage while the engine is running. It must be between 13.75 and 14.75 volts. If it is low, suspect worn brushes if it is an intermittent problem. A poor connection in one of the wires leading to the generator can cause intermittent operation too, but worn brushes are a lot more common.

Sorry but I'm not familiar with your generator. I own a lot of older Chrysler products and on their alternators the brushes can often be replaced without removing the unit from the engine, and replacements cost around 3 bucks. On their newer models from the late '80s on, they use Nippendenso alternators and again worn brushes at around 150,000 miles is the most common failure. Replacement involves removing the rear stamped steel cover and unbolting a small inexpensive assembly. That too can often be done without removing it from the engine on many models. That brush assembly costs $9.00.

On some imports the brush assembly is built onto the internal voltage regulator. Those can get pretty expensive and you might find a rebuilt generator is cheaper.

My best suggestion is to head to a pick-your-own parts salvage yard, find a model like yours, and do some experimenting there. If you live anywhere between Ohio and southern Georgia, there is a real nice chain of yards called Pull-A-Part where you pay your buck, throw your tool box in one of their wheel barrows, and you can spend all day there. People and customers are real friendly, parts are very inexpensive, and the yards are very clean and well-organized. You can do an internet search to see which yards have cars like yours but that won't tell you the colors, options, or which parts have already been removed.

SOMETIMES THE "NEW GUY" OR THE "IN A HURRY GUY" DOES YOUR TESTING

. IT HAPPENS!

NOT FEEDING THE "TEST MACHINE" PROPER DATA OR NOT USING THE "AMP CLAMP" (A GOOD FEATURE, THAT CAN BE BYPASSED, BY PUSHING A BUTTON)

TRY ANOTHER "NAME" PARTS STORE FOR A SECOND OPINION, IF THEY DON'T HAVE YOU TURN ON LIGHTS AND BLOWER MOTORS FOR A DRAIN TEST. FIND ANOTHER

BELOW IS THE ONE CLOSEST TO ME, AND I FREQUENT QUITE OFTEN

REMOVING THE ALTERNATOR MIGHT BE QUITE A TASK IN ITSELF---"GOING IN" AIN'T REALLY HARD. IF YOU KNOW WHAT YOU ARE DOING (NOT KNOWING MIGHT NOT BE SO GOOD!)

EVEN WITH NEW BRUSHES, YOU STILL HAVE A STATOR THAT "SHOULD" SOME MACHINING---AND THEM BEARINGS/ BUSHINGS JUST AIN'T GETTING YOUNGER EITHER

MOST PEOPLE OPT FOR A REMAN OR NEW ONE. ALL MENTIONED ABOVE SHOULD BE "SQUARED AWAY" INSIDE EITHER ONE YOU GO WITH. BOTH WILL HAVE A LIMITED LIFETIME WARRANTY. THE REMAN IS LESS EXPENSIVE AND "REMAN ANYTHING" HAS WORKED FOR ME FOR YEARS

I RECENTLY PURCHASED A JEEP BATTERY. AND JUG OF WASHER FLUID TO "GET ME" OVER THE $100 MARK

THIS ALLOWED ME TO USE "ONE" OF MANY PROMO CODES I COULD FIND FOR THE STORE. THIS PARTICULAR ONE SAVED ME THE MOST FOR MY PURCHASE AMOUNT, YOU GOTTA DO YOUR HOMEWORK TO GET THE MOST OUTTA WHATEVER YOU FIND. THIS "SYSTEM" WORKS AT AN AUTO PARTS STORE. ELECTRONICS STORES. STEAK HOUSES. USE YOUR IMAGINATION!

JUST FOR GIGGLES, I PUT IN THE SAME PROMO CODE I USED ( "FABU" ) AND PUT YOURS IN MY CART THEN RAN YOURS THRU THE CHECK OUT. STILL WORKS GOOD."SELECT STORE" AND "PICK UP AT STORE". ALL YOU GOTTA DO IS WAIT AN HOUR. CODES DO EXPIRE. NOOOO! I TOOK IT OUT OF MY CART, YOU'RE SORTA BACK ON YOUR OWN!

I AM NOT TELLING YOU TO RUSH OUT AND SPEND $$$.I'M JUST TRYING TO HELP IF YOU HAVE TO. NOT JUST FOR THIS ISSUE, BUT DOWN THE ROAD TOO

THE MEDIC

Doesn't sound like you have a drain because it cranks, starts, and runs, then the problems occur while it's running. If the generator was working you wouldn't have trouble once the engine is running.

You also have to look at the circuit that tells the voltage regulator when to turn on. Most commonly that was done through the battery warning light circuit on the dash and the ignition switch. If there's a break in the wire going from the battery light to the voltage regulator, the regulator will never turn the generator on. That's why you have to measure the battery voltage while the engine is running, and while the problem is occurring. Another clue is the battery light won't turn on when you first turn on the ignition switch.

Another potential problem is one defective internal diode of the six. Output voltage will be normal or even a little high, but the maximum output current you will get under a load test will be exactly one third of the rated 80 amp output. 30 amps may not be enough to meet all of the needs of the car. A fuel pump can draw 6 - 8 amps, plus you have the fuel injection system, the ignition system, heater / AC fan, radio, various computers, and a few lights, and if all of that together draws more than the generator can deliver the battery is going to supply the rest until it slowly runs down.

A lot of generator bench testers at auto parts stores only test for some output current and for the voltage it regulates at. They usually aren't strong enough to run them at full output so all they're looking for is some output. You're much better off having the entire charging system tested with the generator on the car. Most professional load testers include a "ripple" test. DC generators are all three phase generators. When one diode is defective the ripple will be very high because the voltage drops one third of the time because of that missing phase. The bottom of this page will explain ripple and what causes it to be high:

http://randysrepairshop.net/charging-systems.html

If it's high, and you can only get 25 - 30 amps during a load test, there's a bad diode. Due to their cost it usually doesn't pay to try to replace them. It's better to just replace the entire generator.

Just to add to this one did you buy the alternator at auto zone the one you replaced 2yrs ago?Also taking it apart to check the brushes voids the warranty should have checked for a warranty before taking it apart. You never checked to see if the alternator was charging or not before taking it apart?

Do you have a multimeter?

You do a load test at the battery. You don't have to get to the wires behind the generator.

If it turns out to be not charging you will have to get to the back of the alternator to check the alternator inputs.