Clamp it with a Zener Diode somewhere on the 12v output line. All excess
current will bleed off.

Thanks Clams,

I know I could regulate it easily. You are an old Merc fan and you know how to
fix it so you must have run into this before. What I am looking for is the
reason its doing this now after it ran fine all those years. Everything is
still in spec electrically. I really find this interesting. All the posts on
the web about it and no one can or has answered it yet.