John Deere Gen-Set (Certified) Marine Engines PowerTech 4045 Series Generator Drive Marine Engines 4045TFM85 – 1800 rpm 4045AFM85 – 1800 rpm PowerTech 6068 Series Generator Drive Marine Engines 6068AFM85 – 1500 rpm 6068AFM85 – 1800 rpm 6068SFM85 – 1500 rpm 6068SFM85 – 1800 rpm PowerTech 6090 Series Generator Drive Marine Engines 6090AFM85 – 1500 rpm 6090AFM85 – 1800 rpm 6090SFM85 – 1500 rpm 6090SFM85 – 1800 rpm PowerTech 6135 Series Generator Drive Marine Engines 6135AFM85 – 1500 rpm 6135AFM85 – 1800 rpm 6135SFM85 – 1500 rpm 6135SFM85 – 1800 rpm