NOTICE: BEFORE YOU PLACE YOUR ORDER. Our 33S877-ET 19 HP Briggs & Stratton Engine Kit is a replacement for most Kohler Courage Single Cylinder Engines On Exmark, Toro & Other Brands Of Zero Turn Mowers. This Is A Complete Direct Replacement Conversion Kit. Packaging, Engine Will Be Inspected By Our. Engine Mounting Holes Are Not Threaded You Will Need 4 5/16″ x 1-3/4″ Bolts, Washers, And Nylock Lock Nuts. Briggs & Stratton 33S877-FLG 19 Gross HP Engine. 1 X 3-5/32 Crankshaft. Muffler For Zero Turn Mower. You may need to reroute fuel lines, change throttle controls, depending on your mower model. We Are A Real Brick And Mortar Store, We Have Been In Business For Over 40 Years!