Q: When I install a new alternator and start the engine, after about 45 seconds the alternator gets very hot and starts smoking. I’ve gone through 2 alternators so far. Can you tell me what the problem could be?
A: Sounds like the battery may be defective or shorted. The alternator is trying to put out too much current. Alternators are not designed to run at 100% amperage output for long periods of time. They are designed to keep a battery charged as energy is used. Check to make sure you don’t have the polarity reversed on the battery. The red wire goes to the positive and the black wire goes to the negative. Trace the negative wire and make sure the ground connection is tight and not corroded. Be sure your battery terminal ends are also clean.