I ran my NEW JD S100 mower W/17.5 Hp. B&S M31 motor for 12 hours and I noticed oil running down from under the flywheel making a mess of everything. I have tools and knowledge so I pulled the flywheel to discover a soaked upper crank seal. Is Briggs quality QC slipping? I ordered this OEM seal and replace it myself. To heck with the warranty hassle, I saved $100 (for pickup/delivery) and a whole bunch of time by fixing it myself, a simple job. Plus, I know It’s done right. I also have a camshaft ready to go if needed). Now everything is fine. I recommend.