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Hello Classic enthusiasts. My 1977 datsun 280z car is almost up and running. The problem is a little hard to describe. I replaced the battery and the car ran fine. I notice the car started to lose cranking power after 8ish car start ups. Around this time, the car would struggle to crank. I charged the battery right up and the cranks beautifully. At first, I thought my alternator is not charging my battery (which seems to be the case). I went through the "Alternator not powering battery" thread and could not assess my situation. I did some testings on my car with a multimeter and found some questionable data. From the battery, Trial #1 12.6v - Engine Off 13.6v - Engine Idling 11.88v - Engine Idling w/ headlights on 11.90v - Engine Idling w/ headlights on and max fan 12.90v - Engine Idling w/ lights and fans turned off Trial #2 12.42v - Engine Off 13.34v - Engine Idling 12.06v - Engine Idling w/ headlights on 12.01v - Engine Idling w/ headlights on and max fan 13.36v - Engine Idling w/ lights and fans turned off It is weird how I got different voltage readings for when car is at idle and when car is under load.. I do have to bring up that about a year ago when I was working on my car, when I tried to start my car the fusible link caught fire. Weirdly enough, it was the alternator and Relay fusible link. I replaced the link and the car starts up fine but then the car battery would not be charged by the alternator. The 1977 came with a voltage regulator that is located below the fusible link box. Would there be any chance that when the fusible link caught fire, it shorted my voltage regulator? What could be the problem being that my car is not charging while under load? If I read through a series of forums correctly, I believe that the the voltage should be around 14V while idling or underload.