My Snapper mower has a Briggs and Stratton 8.5 HP motor with an electric start. When the engine is running it produces the same sound you would get if you pulled on the starter rope with the engine running. I have determined that it is the result of one of the "teeth" in the recoil starter mechanism being struck by the spinning top of the motor. It does not appear to be doing any damage, but the noise drives me nuts. Other than replacing the entire recoil mechanism, any suggestion for fixing the problem?