Abstract: An internal combustion engine is connected to a fixed displacement pump normally having its inlet connected to a reservoir and its outlet connected to an accumulator. To start the engine, selectively operable valves connect the inlet of the pump to the accumulator and the outlet to the reservoir to drive the pump as a motor to rotate the engine. Also, a fixed displacement motor has an inlet connected by a forward solenoid valve to the accumulator and pump and connected by a brake solenoid valve to the reservoir. The motor also has an outlet connected to the pump and the accumulator by a reverse solenoid valve and connected to the reservoir by a neutral solenoid valve.