Have a YM with Briggs 6HP Quantum.Ran good last time I used it.Today it will not start.Its getting gas but has no spark.Checked it with a spark checker and also by grounding the plug.Will not fire.I am assuming the coil may be bad.Have never had a Briggs coil go bad.Anything else I should check?This is always garaged so no rust on flywheel or coil.Spark plug is good.