Re: Does the tach run from stator AC or is it DC?
I am a bit confused. I am reading that the tach runs off the stator AC pulses? If so, why does a faulty rectifier affect the tach?
If the rectifier takes the AC pulses and converts to DC, why would the rectifier integrity affect the tach?
The tach counts the AC pulses as a reference for how fast the motor is running.
The tach takes the AC pulses off before the rectifier, that is true. But you would have to understand the theory behind a full wave rectifier to make sense out of it. Let's just say that there are four diodes, each passes electricity in one direction only. If one of the diodes is open or shorted, the alternator can't properly "see" the battery or ground, whichever the case may be, and therefore the alternator's stator circuit is either open or shorted. If you want the long story, it would take me awhile to explain it.
