Bought a power torque mower cheap, started easily but a lovely knock. Thought a complete rebuild might be required but got it cheap enough, I was happy to wreck the block and keep carb,coil and bits for spares. Upon turning the blade plate by hand, no play or rumble was evident. On a hunch I popped the motor off the base and pulled the flywheel off. Voila! Worn enough to knock nicely. Fitted another flywheel and Bob's your Aunty! Away she purred ....as good as new!
Imgur, flywheel 1 Flywheel 2 
