Alternator Removal/Test
I have been having problems with my electrical system for quite some time. I have had problems with my (relatively new) battery not holding charge, as well as the alternator overcharging to up to 15.5 volts. (Factory spec is up to 14.5 volts) I have had the battery checked several times, and after some use, it would not hold charge, however it would show "good" on the test at the parts store. I eventually convinced them that it was not "good" by leaving it there, and showing them that it lost charge overnight. After getting a new battery, I was still having the same electrical problems, so I checked wiring and fuses. I found nothing obviously wrong, so I proceeded to remove the alternator (pics below), and have it tested. For the removal, I used Stealth 316 Alternator Removal Page as my primary source of directions and information. After removing the alternator, I had it tested at two auto parts stores, and one said that the alternator was working fine, and one said that it was bad. Next, I took it to an automotive electrical specialty shop (B&M Electrical in Lafayette, IN), and it was tested there, and I was told that it was okay. After describing my problems to him, he suggested to check the wires to the plug on the alternator for the correct voltage. (It should give the same voltage as the battery). He said that if it did not read the same voltage as the battery, it could lead to overcharging, which could cause the battery failure. I checked the alternator plug (plug can be seen in pics 3 and 4 below), and the voltage was correct. I then reinstalled the alternator, and the system was still overcharging. After shutting the car off, I noticed that the plug to the altnerator (that I had just tested), looked loose. I clipped it securely in place. (Note that it took a LOT of force for it finally to lock/snap but when it did, it felt secure). After that, I restarted the car, and it held steady voltage from 14.2-14.4 volts. This seems to have cured the overcharging problem, and only time will tell if it was the real culprit for the overcharging and/or battery failures. The accessory belt also showed signs of age with some cracking on the ribs of the belt, so I replaced it when the alternator was reinstalled.
Removal Pics
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