How are you measuring that? 164 volts is roughly the peak value of the sine wave but the RMS value should be lower. That's assuming you are getting 60 cycle current.
There really is no "voltage regulator" that I am aware of - the windings on the armature pretty much govern the output, though it depends on the motor RPMs to make it come out right. If the motor is not turning at the right RPMs, you won't have 60 cycle current and your meter may not show the right AC voltage.
2004 American Tradition; 2014 Buick LaCRosse
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