"Dave Liquorice" wrote in message
ll.net...
On Sun, 7 Sep 2008 15:53:27 -0700 (PDT), Peter C wrote:

I now find that on the chain drive side the top pulley can be turned
by hand when the engine is not running, also when the problem shows
upon trying to cut the lawn the chain is not revolving.,

Maybe the woodruff key has sheared or dropped out? If it has a woodruff
key that is.

http://en.wikipedia.org/wiki/Woodruff_key


Is this the sprocket (not pulley) on the end of the engine crankshaft? It
has a woodruff key, it also has a taper, and is secured by a left hand
threaded nut. I'd say that this was loose. The woodruff key may well be
missing.

Steve