Alternator question

I'm trying to decipher an intermittent charging/starting problem. Before I get too in depth, quick question.
Should there be voltage when measure from battery +ve to case of alternator? I did quick continuity chk and was surprised, so I measured and I'm getting 12.2 with everything hooked up but car off.
I'm thinking alternator is shorted internally?
Anyone?
67 barracuda SB MP elec ignition
Thanks
Steve