I have a 1972 chevy pickup tht I just replaced the alternator on. When I did the test by removing the negative battery terminal while it was running. It shut off, the alternator is brand new. Any suggestions?
The battery should not be disconnected as part of any test. Maybe a fusible link has blown. My memory seems to recall the links are at the battery cable connection at the starter solenoid. These may appear as lengths of heavy red wire.
Make sure the red dashboard alternator lamp is operative also as that influences the alt. charging.
When I did the test by removing the negative battery terminal while it was running.
What test were you trying to do? Where did you learn this?
That procedure is asking for trouble, either with your new alternator - by killing it, or with electronics on your vehicle - by frying one or more of them.
The real test is to use a volt meter or multimeter to read the voltage at the battery. Pulling the battery cable while the engine is running can damage the alternator. Forget that method.
with electronics on your vehicleOn a 72 chevy p/u? They didn't even have electronic ignition then. On a newer vehicle I would agree. In the past I have had problems with the connections at a junction on/near the fender, horn relay (believe it or not), and burned out alt light. Also once had an issue with an aftermarket amp meter that went bad that would not allow charging.