New alternator, engine harness, battery. Still no charge

[astat1]

I thought my issues were over after I cleaned up the ground at the voltage regulator. After coming home from a show this weekend my alternator bolt broke off leaving my alternator swinging (no other damage). I have replaced the bolt and the old alternator but re-experiencing the same discharge situation. I put in a new 45 amp alt. The engine harness is several days old (made for ECU), the battery is like new and holds a charge at 14 volts. The alternator gauge shows a hint of a positive deflection when the rpms are increased but still only about 12.5 volts and the dash gauge in the negative. Should the alternator gauge be active when the key is not in the ignition (a further negative deflection when lights are on with no key). Battery poles clean and I added a better ground to the voltage regulator. I also changed the voltage regulator. All connections at the alt are tight including belts (also new). Any ideas? Thanks.....I'm electronically challenged.
1970 Coronet with electronic ignition

[Nacho-RT74]

-stock 45 amps alt definitelly doesn't charge at iddle.

-anytime you have consumption on car you'll have discharge reading on ammeter. Since stock alt won't charge at iddle, ammeter will show some dicharge with engine runing too.

-simply open the door you will have Discharge reading ( courtesy ligths, dome light )

-Key in and on RUN definitelly will show also a discharge. at that moment is being feeded the cluster, the choke if equipped, the regulator, Ballast and all accesories if some is turned on.

-To check for voltage on batt with engie runnig if you want fit the high iddle speed cam on position ( choke cam ) and won't need to increase the low iddle screw

[astat1]

Thanks again Nacho, but I can't get anywhere near a charge state regardless of how high I rev my rpm's. Its a steady discharge state no matter what.

[Needa68]

astat1: It might be best to do some basic circuit tests at this point. Suggest you disconnect the battery then check the two wires that connect to the alternator. The black wire should be connected to the alternator terminal labled BAT. The dark green wire should be connected to the terminal labled FLD. If they are connected properly, remove the center plug from the bulkhead disconnect (located driver side on firewall). In the connector on Pin P you'll find the black wire that connects to the alternator BAT terminal. Disconnect the wire fron the alternator then using an ohm meter determine if the wire is shorted or has very high resistance. If it has either condition replace the wire reconnect your battery then test the system by starting the engine.

If the black wire checks out properly perform the same tests for the dark green wire connect to the FLD terminal on the alternator. This dark green wire runs to the FLD terminal on voltage regulator. Disconnect the wire on both ends before running the rests. If both wires check out properly do the following.

While you have the center connector removed from the bulkhead disconnect run the same tests on the dark blue wire connected to the ING terminal on the voltage voltage. This wire terminates in the center plug at the firewall on Pin N which is just below Pin P. Disconnect the dark blue jumper wire going to the ignition ballast resistor before performing the tests. If that wire checks out good move to next test.

Test the fusible link circuit. This circuit runs between Pin J in the center cable connector to the B terminal on the starter reply. It shouldn't be hard to identify this circuit because a fuse casing is built into the wire. From Pin J in the bulkhead disconnect this circuit runs to one side of the amp meter in the dash.

If these tests don't locate the problem you'll need to go through each of the remaining circuits drawing current until you find the problem. I've seen people remove circuits at the fuse box to find a shorted circuit. If you chose to do this be sure to disconnet the battery. I prefer to remove the negative cable when disconnecting the battery. I hope this helps!

[Nacho-RT74]

or, simply put the key in RUN and test uf you are getting 12 volts between green wire on brush and chassis.

if not

check for 12 volts on blue wire at regulator

If yes

-check for good green wire
-check gor good grounded regulator
-probably damaged regulator.

If not

-check for good blue wire conditions
-check for propper plug and tight at engine harness bulkhead plug
-check for power on blue wire on back of bulkhead
-check for power on ignition switch prong

you can also bypass regulator, jumping between green and blue wire ( or removing and linking ). becarefull on that moment will get FULL JUICE at alternator oce start tup engine, so make it at iddle, not more.

If get juice, then same as explained above, damaged reg or bad grounded

what of course is not a reason for fail is the blue wire at bulkhead since if was bad, then car wouldn't start up... but in another cases is another part to check

[astat1]

Thanks for the replies. I have checked the bat (on alt) connection with a voltmeter (getting 12.4 volts at high idle and about 12.2 with car off). Isn't that a bad alternator? I will check the rest of the recommendations now.

[Nacho-RT74]

not necesarily. If you don't have input on alt you won't have output. Altenator is not a GENERATOR... needs to be feeded. regulator feeds to create the internal magnetic field ( thats why brushes call FIELDS on alt ) for a while more power needed, Regulator increases magnetic field, then gets more output from alt stud.

so if you have bad regulator or wrong feeded regulator, this never will feed alt. You can have a good alt but not good reg or related wires

[astat1]

Well it turned out to be a faulty field (blue) connector on my new engine harness from Jack's. I will call them Monday and see what they have to say.......