My Craftsman lawnmower runs great but it will not move.

Brent, August 2008

if the belt is on the machine and it won't move then the sheer key in the pulley on top of the transaxle has sheered. Reach under the rear of the machine and try to move the pulley, if it moves the key is sheered.
hope this helps you:

Mickey-G, August 2008

Brent
My husband has had a similar problem with his Mountfield mower. The split cotter pin on the drive shaft has probably sheered. It is there to prevent the lawn mower from overloading the engine. You can replace it quite easily and it will only cost a few pence. Can be obtained from a lawnmower supplier or any hard ware shop.

Suzie, August 2008