I have a Honda HRX217K3HYA. My son was mowing, and hit a piece of rebar. It sheared the flywheel key. I replaced the key, however, when the blade is engaged, it shears the key again. yes, I am a slow learner, and went through two of them. I took the Blade adapter off, and it feels like the bearings on the adapter are shot. Could this cause the key to shear when the blade is engaged?