Craftsman 91728903 Manual. View or print the Craftsman 91728903 Manual below to learn more about maintenance information and troubleshooting tips for your lawn tractor. The Sears Craftsman 917.28903 is a 17/5 horsepower lawn tractor with a 42 inch mower cut and 6 speed transaxle. This model was one of the first lawn tractors under the Craftsman brand to have a low emissions engine. The manual also covers safety issues and how to use the tractor on slopes. If you need parts, we suggest Sears Parts Direct as they have millions of parts for lawn tractors and other lawn and garden equipment.