Diagnose, repair, and maintain diesel engines used in power generation, marine propulsion, and agricultural machinery; Detect mechanical and electrical faults by using gauges, instruments, and laptop computers that check machine electrical and electronic circuitry, fuel injection systems, hydraulic systems, engine speed control, engine condition, and performance; Dismantle and rebuild machine components to manufacturers' specifications; Use welding equipment, hand or machine tools to manufacture or repair parts. Typical work involves electrical and lighting repairs, brake work, satellite communication/tracking system repairs, external engine components, AC blower motors, repairs to trailer doors and seals, some bodywork, and chassis/suspension work.