Somewhere on teh intarwebs "Muddymike" typed:
"S" wrote in message
news
The `cotter` is still intact as I took the blade off.

The cotter I referred to is the one that locates the flywheel on top
of the engine, not the blade.

It's a Woodruffe Key rather than a cotter pin, and yes, I've known one to
shear when the engine stopped suddenly and the flywheel didn't. However,
more modern engines don't seem to have such heavy flywheels as the older,
slower-revving ones so not so likely IMO.

It's my opinion that there's likely something far more serious wrong with
S's mower. :-(

My educated guess? Same as Charlie's. Bent crankshaft. That's why I'll never
own a mower with a 'bar' blade again. My mower has a disc with two 'swing'
blades bolted to it. Not much to catch on anything heavy, certainly not
enough to stop the engine suddenly enough to cause damage.
--
Shaun.

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