Just got a 98 Forman 450sw in the shop today. The owner said it was smoking and was hard to start then it wouldn't start. It had very little compression . Pulled the head and I could move the edges off the piston Up and down. Making the piston slightly crooked in the cylinder.. One side of the piston is worn bad. And there is a small amount of play in the rod side to side. How much play is to much play and what would have caused this?