White powder on the battery tray,sometimes can hear the battery sizzling, have added water. I went to the local auto parts store and they put a meter on it.Checked out as good( 15-16 volts). Then I revved the engine and the needle intermittently started fluctuating into the overcharging zone.Auto parts guy said it could be alternator or regulator. I thought alternator only put out what it had coming in. Is it the alternator or regulator in your opinion? Thanks, SCott! :confused:

Alternator creates voltage, current flow. Voltage regulator regulates voltage out of alternator. 15 to 16 is too high to begin with, sounds like regulator.

A Wells part number VR715 is the best buy on a regulator. Around $11.00 at Auto Zone. Disconnect the battery before installing it.