Small Engines (Lawn Mowers, etc.): techumseh compression lock, key way, lawn mower

Question
Hi I have a small techumseh 4 stroke lawn mower {sorry i don’t know the size or model number} last week i it started it & it started banging & rattling terribly i checked the blade pate & found it was loose i tightened it  & tried to start it & it kicked back & pulled the cord out of my hand I tried it again & this time it broke the cord  i fixed the cord tried it again  & it broke the cord again i pulled the spark plug out tried it again & it turned over OK so i pulled the head off thinking it had a stuck valve but all seemed OK you can turn the motor over by hand turning the pulley on top but when you try to pull start it gets compression lock & yanks the cord out of your hand. Any ideas ?
Cheers Wayne

Answer
Wayne
What you problem is the flywheel key way must be sheared or not in line with the flywheel.Pull the starter off and any other parts so you can see the flywheel to make sure that the key way is lined up with the flywheel. This engine is out of time that is why it is kicking back.