Is anyone here good with small engines? I have a Cub Cadet rider with 16.5Hp Briggs. I was mowing the other day and the engine slowed down and then puffed smoke then died. Will not crank now seams like it has seized up for some reason. It has plunty of oil for i check it before I mow everytime. Does anyone have any Idea why this happened and do you think a rebuild is worth while?