If we keep killing batteries and its not the alt then it must be the voltage regulator ?

Keeps dying? Do you have to boost it? The voltage regulator is internal to the alternator. Is there power to the alternator to turn it on? LOts of could be's here without more info

The Charge lamp comes on with the Alternator fails to keep battery charge going. (lots of way to fail, and ALT Is 100% good) it's a system. each part of it must be good, end to end.
so...
i put my voltmeter across battery, i start car, i see 13.3 to 15vdc, alt is good.
no? , i see now, 12.2v. ALt is dead, (i didnt say bad) and battery is sightly discharged, 12.6v is charged. (key off, rested voltage)
This 12v tells me the ALT is shut down. only why is the question.

how can any charge system fail,
bad battery tops the list here, they LOVE to fail.
1: belt slips.
2: belt missing
3: bad alt.
4: bad wires to ALT . (corrosion on any wire or lug)
5: fuses blown , any listed below.:
your alt is not an ECU controlled, alt ,its 100% self contained

did you ever remove the ALT and blow the 100 amp fuseable link
the first step of any alt pul, is the pull the NEG, battery lug or BOOM.

im logged in to alldata.com so can you.

and what do i see.
a 5 wire ALT. one is the frame ground, so it must not be rusty or..... it fails. frame to engine block. no rust here.

wire L , yellow.goes to dash LEDs (alt failure idiot lamps) (this works)
wire. S white goes to ALT 5a fuse, is it blown?
wire :B B/G color, goes to the 100 amp link fuse. (blown>?)
wire IG Red-white, goes to a fuse marked 10A gauge.

i think the IG wire is the voltage sense wire.
no sense, no charge. I think the whole I/P dash cluster goes dead when this fuse blows.

The S wire is the boot strap voltage sense, it wakes up the regulator .
if open , the reg stays asleep, as does ALT.
Alternators can not self start, the regulator has boot strap device
that cures that. called self excitation. so this wire is critical.
All wires except the L wire is critical. in this case.

the B wire is the big wire, it charges the battery . 50amps or more..

any of the 5 paths open , kills the ALT dead.
The REG inside the ALT can also shut it down.
eg: battery bad, with huge cell resistances. total.
eg: overvoltge for any reasons. including attempts top run car with no battery, (dont ask)
eg: over current (battery cells 1 to 6 shorted) or 25 KC lamps added.
eg: over temperature shut down.

that is about it.

voltage regulator. it may be in the alternator, or remote mounted. ((the alternator can be charging, but if voltage regulator is'nt working then it won't allow voltage to get back to the battery to keep it charged

A 76, huh, let's see, I don't know if that had the regulator in there or not. It sounds like the alt died, but maybe not. It won't run without the alt. And will only last about 20 mins on a full battery. I would take the alt off and get it back to the store to have it checked. That would be the quickest way to tell, just because it is new doesn't mean it is good. Don't keep on killing the battery, it can only handle so many drains. Hope this helps.

You may have a voltage drop in the battery feed to the Alternator through the fuse link and into the battery. Check the charge rate at the battery feed on the Alternator, it should be at least 13.8 volts, if it is, locate the fuse link and check it there on both sides of the link, if its still good, follow the cable back to the battery checking the voltage as you go. If you find that the voltage suddenly drops across a connection or the fuse link, remove and clean the connection or replace it if possible. If the voltage at the back of the Alternator is less then 13 volts, then the new Alternator may be faulty. If the voltage is higher then 15 volts, then the Battery feed to the Alternator is bad and MUST be fixed. Check these voltages with the engine running but watch out for moving parts ( fans etc). If you think the battery feed to the Alternator is bad, shut the engine down and recheck the voltage at the Alternator, it should be at least the same as it is across the battery. If there is no power to the Alt when the engine is off, start at the fuse link, checking for voltage and trace back to the alt until you lose the reading. If you get no voltage at the fuse link, track it back to the battery. The voltages at the battery and Alternator should be the same or only have a difference of half a volt, any more and you need to locate and fix the bad connection. DO NOT run the Alternator without the load of the battery for extended periods as this will damage the Alternator. The Alt needs the internal resistance of the battery to function correctly. If the voltages from the battery to the alt are correct, check the regulator wiring. If memory serves, there are two small wires to the alt which are in a small plug into the alt and one thick cable which connects to a bolt on the alt. The thick cable is the battery feed, the two small cables are the regulator feeds. One small cable operates the warning lamp in the dash cluster and the other is another battery feed which gives the regulator an indication of the charge rate AT THE BATTERY so if this one is missing the regulator will also cut out. The warning lamp wire serves as an indication to the regulator that the ignition is turned on and makes the alternator charge. This lamp should be on with ignition on but engine NOT running and should go out when you start the engine. If this lamp does not light up at all, suspect a broken or missing warning lamp connection or faulty regulator.A blown warning lamp bulb will also prevent the alt from working, this is because the bulb is fed with power and is grounded at the alt through the regulator and exciter diodes, feeding the regulator with power until the engine starts, then the alternator output essentially puts power to both sides of the diodes causing the lamp to extinguish. A diode is a one way valve for electricity and the regulator is inside the alt. If you suspect a faulty alt or regulator, remove them and have them checked by an autoelectrician. Unless you know what you are doing, DO NOT attempt to disassemble the alt as you can cause catastrophic damage and have to purchase a replacement alt. You may also void any warranty by disassembling the alt.. Undertake these tests and if you have any questions, email me here: [email protected]
Dave.

If you disconnect the battery for 20 min it should kill all memory and reset everything.If not you charge is still low charge up your batt. with a charger.and test your alt. output 13.9-13.7 you have to check the book.I'm not to sure on that.You might have a voltage regulator problem bad batt. Or somthing is hooked up wrong. Mabey the old alt was fine. Have the batt. tested. All alt. well most are rebuilts so you might have a bad one it happens.Make sure that it's putting out a charge.
Loose alternator drive belt or loose or corroded battery cables. The battery itself may also be bad.

A bad ground kills alternators and charging at full capacity too long does them in. The charge rate read with a meter should be 1.6 -14.2 No higher or lower. The lower the voltage the higher the ampereage. So @ 10 volts the alternator is working real hard and that causes the alt. to overheat enough to damage solder connections. Hence,the term "slinging solder. The bad ground, battery or alt, causes output spikes and regulator damGE. cHECK ALL YOUR CONNECTIONS AND THE VOLT RANGE OF ALT OUTPUT. iF IT'S CONSISTANTLY TOO HIGH, YOUR BATTERY SHOULD BE QUESTION.. The voltage should be low after cranking and starting but statart climbing after a minute or so as it recovers.

Usually when the battery light comes on it means there is a problem with the alternator. It means it is putting out less than 12.2-12.5 volts.

take it in to an accredited auto electrician and have the voltage regulator checked
batteries die from under charge or overcharge and that is the job of the regulator to keep the voltage at 14.5-14.8 volts DC

I believe that your vehicle has an external voltage regulator for the chargeing system.just FYI the spec on all vehicle chargeing systems when the vehicle is running should be 13.8-14.2 when checked with a volt meter.I would start by checking the voltage regulator.If it isnt external than your alt is bad.