I purchased a Poulan_Pro Self Propelled Lawn Mower Model PR160OY21PR, I was adjusting the height position to medium. I was able to remove the bolt and nut and align the sides to the correct position but cannot tighten and reasseble the the nut (532 18 88 21) and knob (532 75 11 53) because the nut does not extend far enough past the hole to expose enough thread to tighten the nut onto,
Thank you.