Voltage issues

[mbr]

On an '82 caddy diesel, 1.6, 65 amp alternator: I'm getting a low voltage reading, even at the battery. It reads 13.5 DC volts, just over 12 when any electrical accessory is on. Should it read DC volts? Switching the meter to AC, it shows around 26-28 volts.
On the alt there is supposed to be a plug on a 3-prong terminal. There are 3 individual connectors instead of the plug. Can it be the connectors are on the wrong terminals?

[QuickTD]

The low output combined with large amount of AC riding on what should be the smooth DC output of the alternator leads me to believe the alternator has a shorted diode. I would assume that the alternator is making a whining noise as well. A rebuilt or good used one would be the way to go. The 3 wires are probably connected properly, if they were not the alternator would likely have no output at all.

[mbr]

I probably need a new alt. Are there options beside the 65 amp Bosch? Will a higher amp one from a gasser work?

[shwartzbewithyou]

If it's just the diode pack and not the stator you can buy a cheap kit for it on http://www.autopartsonlinecanada.com/ or any of the worldpac sites.  It's reading low, but that doesn't always mean she's completely toast.