Alternator whine, replaced parts now im stuck!
 

My first post here, I did search a bit but couldbt figure out too much. So here is the story.

Well first the car is a 1965 Chrysler 300, with a 372c. (thought it was a 383, but after some research I'm not really sure)

My alternator started whining really bad. So I replaced it. I didn't realize it had but upgraded to the 70+ style with a new style regulator. From there I realized put a new older style regulator, and re did some of the wiring to under the upgrade.

So now it seems to charge, hasn't left me stranded yet, but still whines, so I'm back where I started.

Symptoms I noticed before I replaced the alternator where high voltage, around 16v on the highway. Then it dropped down to 12ish as the whine got louder.

Now I'm back to a light whine at first, then after cruising on the highway for a bit it whikes loud again.

Any advice would be greatly appreciated!

marcello -

Hate to say this, but are you sure you didn't over tighten the belt?
There needs to be "thumb" pressure slack on the longest span.

Archer

What condition is the battery in if its got a shorted cell it will make the alternator work hard and could even burn it out. The whine is caused by the Alt. doing heavy charging while its running disconnect the negitive side of the battery and see if the whine goes away. I would have the battery tested...Bill

Where are you hearing this whine? I would call whine "normal" if it's coming from the alternator itself when charging.

As said above, might be a bad cell in the battery.

WHAT IS the voltage running at the battery? A very common problem in all these cars is VOLTAGE DROP in the wiring harness or ground circuit, or both, which drops battery voltage TO the regulator and causes an overcharge condition.

There is nothing wrong with a late alternator and an early regulator, all you need do is ground one field terminal

Use the much better late 70's "squareback" rather than the older "roundback."

Just because you replaced the alternator does NOT mean that the new one is good. An alternator with a defective stator or bad diode(s) can still charge somewhat but might whine.

Does it "whine" in the radio? This is a sure sign of trouble

Next, you might have high resistance IN THE CHARGING path to the battery.

With the engine running at an RPM to simulate "low to medium" cruise speed, make this check first with the battery "up and normal" and with all loads off, and again with loads on, lights, heater, etc.

Hook one probe of your meter to the alternator output stud, and the other to the battery POSitive post. If your read more than about 1/2--1 volt, there is trouble in this circuit.

The circuit path is alternator stud -- bulhead connector -- ammeter -- back through bulkhead -- fuse link -- starter relay stud -- battery

======================

Check your running charging voltage, battery "up and normal" RPM at "low to med" cruise. Regulator/ engine should be warm. Charging voltage should be 13.8--14.2, and in no case below 13.5, nor above 14.5 If it's high, make the following checks:

1--With engine running as above, stab one probe into the top of the NEGative battery post. Put the other probe on the regulator mounting flange. You are hoping for almost a zero reading, the lower the better. More than .2V (two tenths of one volt) means you have a poor ground between battery and regulator

2--Shut off engine, turn key back to "run." Stab one probe to the top of the battery POSitive post, and the other hook to the regulator "IGN" terminal. Once again, you are hoping for a very low reading. More than .3V (three tenths) means you have a voltage drop problem

That circuit path is.........

battery -- starter relay stud -- fuse link -- bulkhead connector -- ammeter -- welded splice -- ignition switch connector -- through the switch -- switch connector -- back out the bulkhead on the ignition run dark blue wire -- and to the regulator IGN terminal and ballast resistor.

PLEASE read this excellent article, which even if you don't do this mod, points out what goes on:

http://www.madelectrical.com/electri...p-gauges.shtml

Go down the page, there's a simplified diagram which points up the pitfalls in these cars:

The "welded splice" is a factory splice a few inches down into the dash harness in the black ammeter wire. THESE HAVE failed. Top suspects in this type problems are the bulkhead connector, the switch connector, the switch, ammeter connections and the ammeter, and in rare cases, the welded splice.

http://www.madelectrical.com/electri...s/amp-ga18.jpg

372
???

Check the pad on the engine block next to the distributor and see what it say's.

Sorry I haven't revisted this thread. I spent the summer in Europe. Drove the Chrysler the past few days, whatever I seemed to have caused the damaged the first time seemed to destroy the new alternator.

Im leaning towards the dead cell In the battery, or high resistance in the wireharness.

Also i I believe I have the wrong alternator. It's the lower current one, the previous owner had the single groved pulley prost 70 one in there. So when I got the correct year I followed suit with the single lower current one not knowing.

Unless you are running a bunch of electronics you should be fine with the 60 A alt. Have you replaced the regulator ?
DO you have a capacitor hooked to your ign coil ?

I did replace the regulator as well.

Is there any electronic under the dash that has a track record for going bad? im about to head to AutoZone to have my battery and alternator tested. So we'll see from there.

Battery was tested as good, so was the alternator.

I realized im running the 50amp alternator, when it seems it may have been originally equipped with a 2 belt 60amp.

I had a bad battery ground, fixed that but i still have the squeeling.

Marcello