86 cutlass electrical short?

I have an 86 cutlass supreme brougham with the v8, it has a new batt. and alternator, but after a half hour or so the car goes dead. Any help?

I have an 86 cutlass supreme brougham with the v8, it has a new batt. and alternator, but after a half hour or so the car goes dead. Any help?

If by going dead you mean the battery, one of the first things to check would be the belt

Measure the voltage of the battery when the engine is OFF. It should be around 12v.

Start the engine and let it IDLE and then measure the voltage of the battery. If the battery is being charged by the alternator, it should show around 13-14 volts. If the battery is not getting 13-14 volts while the engine is running then trace the wires from the alternator.

Ok, the belt is tight, (its new too) the alt was tested while running, it is good. I read that if the wires from the alt to the starter were bad the car would not start. Is this wrong? My brother said the starter could be pulling juice and draining my batt. How do I check if that is true? Thanks for the help.