Have a really nice running Sears Platinum mower with 7.5HP engine. Went to pull the blade off yesterday and had 3 or 4 pieces of metal fall into my hands. Looked like bearings, but it was actually the small, round 'tabs' that position & hold the mower blade on the main shaft. The blade is pretty beat up, so obviously something was hit in the past - enough to shear off these tabs, but not enough to shear the flywheel keyway. I can still tighten the blade on with the bolt and washer, but just looking for thoughts on repair and whether or not this is a safety issue. Those tabs (not sure of the correct word) likely provide some assurances that the blade cannot slowly spin loose over time.