Some previous owner updated my 51 Styleline from a generator to an alternator. It has also been updated to a 12 volt system. Recently the bearings failed on my alternator, so I got a new one at NAPA. The old one was a one-wire and the new one is a three-wire,but I put a jumper from the sensing terminal to the output terminal. The new alternator was putting out 18 volts and ruined my battery. I took the car to NAPA and they put a tester on it and said the alternator was bad. They ordered my another one, replaced it at no charge, and the new one does the same thing! Can anyone tell me what I'm doing wrong or tell me what to check next? I can't believe I got two bad alternators! I'd appreciate any help anyone can give. Thanks! Posted using the Full Custom H.A.M.B. App!
If I'm reading your post right you only have 1 wire connected to the "DA" terminals? Both wires need to be connected. One is an exciter wire, the other is the voltage sense. If you go to madelectrical.com they sell a kit that includes a plug, terminals, wire, a diode and a diagram to make it easy. But, you can build this yourself if you're a little bit savvy with electrical - just google up da plug and you'll find all kinds of stuff. Good luck.
OK, so I hooked terminal 1 directly to 12V as a test. No switch, lamp, resistor, diode, etc. The output voltage is lower now, however it still exceeds 14.4V. If fact, when I give it a fast idle it goes as high as 16V. This is better than 18V, but I'm still concerned that its too high. What am I missing? Is the lamp or resistor necessary for some reason? Please help. I'm frustrated and about ready to drive it off a cliff! Posted using the Full Custom H.A.M.B. App!
Terminal 1 should be a 12v switched wire. Thats the one that energizes the field coils to make it start charging. Terminal 2 is the sensing wire and it should be connected to a power junction someplace....not connected directly to the battery.
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