Arctic Cat 650 1

I Have 2006 650 4x4 that needs a new engine now, It has less than 120hrs on it. They told me it over-heated, but the fan blows fine on the rad. You tell me. They tried to say it need an oil change, I asked was it out of oil, there reply was no, but needed changing. I haven't got much help out of Arctic cat yet. I have heard that It is a the same as Kalasucky Burton and they have had alot engine problems. Any help from anybody. The warranty just ran out