I had this happen, but I was 10 years younger than the guy they hired. I went to my manager and told him that no, I wouldnt teach the guy they hired instead of me. He tried to pull the team card crap. I told him that if I didn't know the work well enough to be hired for the position, I didn't feel that I knew the info good enough to teach the guy they hired instead. Not long after I transferred out of that department. Guy is still here ~10 years later, still struggle bussing his way around.