1970 oldsmobile 442 has new alternator with internal regulator and new battery keeps going dead

 

Have put a voltmeter across the battery with the engine running at idle and at 1500 rpm to see if its putting out voltage?

 

I think all 1970 442 had internal regulator, but is a firewall mounted voltage regulator still in the circuit?

 

Use an ammeter to see if there is any current drain when the key is turned off and the doors are closed (no interior lights on).
Make sure the lights in the glove box, console, trunk, rear view mirror, etc are not turned on.

 

Where did you get the alternator? I had this same problem 2 years ago when I had bought a new alternator for my '71 from autozone. Two alternators later I found out that the ones that they were selling were bad out of the box. Luckily it didn't cost any extra money because of the warranty.

If you do not have the testing equipment at home, take the alternator up to your local parts store (Advance, Auto Zone, etc...). They will put it on their machine and test it for free to make sure that it is good.

 

Parts stores should be able to test alternators, starters, and batteries OFF-THE CAR. Many do this for free, figuring that if it's bad, you'll buy the replacement from them.







Problem is, "off the car" testing is a crappy way to test the SYSTEM, because you're leaving out the wire harness and the engine heat; and maybe the external voltage regulator as well. Removing the component for testing may "repair" a faulty ground connection. On-the-car testing of the complete starting/charging power team is STRONGLY preferred.