Hello all, new member here. I have an old 12 1/2 hp 38 in cut MTD 7 speed. The deck, all of a sudden, will not lift to the highest notch on the lift lever. Because of this the blades do not disengage. When I try to start it, the lift lever is about two notches from the highest setting therefore the blades are not fully disengaged and the starter is turning the motor and blades. I have checked everything, for broke,bent, obstacles and I see nothing out of place. If anyone can give me some suggestions on what to look for, I'd really appreciate it. Thank You !