Crafteman LT2500 - Have to hold my BLADE HANDLE to keep blades spinni

This riding lawnmower, I MUST HOLD the right BLADE ENGAGEMENT handle down. It does not stay DOWN/engaged. Everything "looks" fine, and cannot figure it out. So I must cut with right hand on handle, left on steering, and no speed control or hand for beer can. I need fix his as cutting is hot work. Any thoughts please help. Belt looks fine, cable looks fine, BUT if stretched out will it cause this problem. Trying to prevent a PARTS CANNON approach. Thank you.