Alternator?

Mattax said

Since things are apart right now, you can do some basic checks of the alternator on the bench.

Click to expand...

Check for shorts beween output and housing (ground), and input (field) and housing.
Check for open field circuit. (continuity between fiueld terminals).
Carefully remove the brushes. Check for wear, and any damage to the insulators and insulating washers. Replace any if needed.