I just got my alternator rebuilt. A 3b 12v alternator from an bj60 in an fj40 with a 3b motor. I was testing the voltage at the battery and at the terminal labled B on the alternator. (I assume where the alternator power goes out to the accessories and eventually the battery. is this correct?) In idle with no accessories going the volts at the battery were about 14.05V and at the b terminal on the alternator 14.2V. It is the same with rpm's higher. When the radio is on, fan on high, and the headlights on high, and the cruiser running higher rpm's (not sure how high as it has no rpm gage) the volts at the battery are 14.05V and at the b terminal on the alternator they are 15.55V. Is this normal. Why the .15v drop between the alternator b terminal and battery in idle and 1.5v drop when rpm's are high.
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