My not even 12 month old Briggs and Stratton 121602 0349 (purchased it as a take off from the small engine warehouse) is suddenly smoking badly. I put around 120 hrs on it, changed oil and cleaned the filter every 25 hrs. Three weeks ago I only could smell a hint of oil, now, it is smoking big time. Is there a chance that this is only the head gasket, or is it better to pay another $110 for the replacement engine special? Thanks for the help!!