[Gary Hill]

The location of most alternators are to close to the bilge,
Buy a new one or get it rebuilt. while that happens run new wires and verify the engine is gounded to the shaft strutt.
After you get everthing replaced turn the battery switch off and veify on any voltage is present (low volt scale),
then do the samething on the low range ohm scale. If anything shows up, start disconnecting electrical components
till it reads zero. rember complete the volt check first so you don't damage the meter.