Small Engines (Lawn Mowers, etc.): 6.75 hp. craftman, briggs and stratton, hp motor

Question
I have a push mower, with a 6.75 hp. motor on it and when i try to pull start it jerks the cord back in out of my hand hard. It back fires alittle to.

Answer
Remove the spark plug.  Pull the string and see if any gas/oil squirts out of the spark plug hole.

Did you recently hit any objects while mowing, mow really tall grass, remove the blade or sharpen the blade, tilt the mower to perform any service?

Is your engine a Briggs and Stratton engine?

Let me know.
Eric