Well...the mower is just your typical noisy mower now, best I can tell - no loud clunking. Guess that fixed the problem for now, though I hope I got the bolt tight enough.
And now that I know the blades for this mower are under seven bucks, I won't stress out so much about using it...
It's too hot to mow. But it's too hot to do anything else, either. Ungh.
Heck... pick up a couple extra and change them weekly, with your rocks ;~D