Is the blade bolt tight?

"Yes-- when I started mowing she did have sufficient oil!"

How about "after"?

YAH...... she had oil after too......
I was really worried it was rod/bearing.
Turned out to be a loose blade.
I put wrench on it and had a hammer ready to loosen it.
Bolt just unwound ....feather-light.

» » » » » » ?? I wonder, am I missing a lockwasher ??

Used some blue threadlocker on before tightening it up again -- after I sharpened the blade.

All's well that ends well. I was going to suggest checking the engine-to-deck mounting bolts, too.

Hard to kill a Suzuki engine!

First search result for "lawn mower developed knocking noise" brought me to this thread. I tightened the blade (it was pretty loose) and bingo! To say that I'm not a small motor (or large motor for that matter) expert would be an understatement.

Thanks for the advice.

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