18.5hp Vertical Shaft Engine XP550This powerful 18. 5hp vertical shaft engine is build for commercial use on medium to large ride on mowers and machinery that is going to be used often. Quality and durability are nothing without support. We carry spare parts and give an industry leading 2 year warranty on design, assembly and materials to ensure you get simply the very best support, whenever you need it. Solid construction and a long warranty mean you can put one of these engines on