Okay I got my tractor back today. It sounds good, just like the day I bought it. The shop told me it was a couple loose valves, they made sure each one was in spec and fixed the ones that were out. I have a good dealer, they came picked it up, fixed it and delivered it again today. Now that is service. And as a plus it looks as if its been washed and greased...!
They did say that the valves should not move again. I will have to speak with the mechanic and ask which valves were out of spec.