Harvester, go to the head of the class! I pulled the plugs and all looked fine. no oil in the antifreeze. No water in the oil. I crawled under the truck to see if the exhause pipe had broken, and when I touchedit, it moved. Back up top I checked the flange, and sure enough, the nuts were loose. I tightened it back up and all is good. I just got back from a trial run and it went well.
As for the blue smoke, I just don't know. It's not doing it now.

Thanks to you all for your input! Stovebolters are good folk.