I purchased a well used 1980 280ZX 2+2, and have gradually, piece by piece, began restoring it to a drivable condition. My problem is the stator of the voltage regulator in the alternator was fried and not charging the battery so I replaced it. Everything was good for a couple of weeks, then it started to squeal on occasion when you first start the engine; like the one I changed did, and keeps getting worse. So I expect it to die any day now. What is causing my Z to eat alternators?