Abstract: A hydraulic system for a motor vehicle having a first flow circuit for steering power assist and a second flow circuit for a radiator cooling fan. The first flow circuit includes a reservoir, a power steering pump connected to the reservoir through a first inlet conduit and a first return conduit, a steering assist fluid motor, and a first flow control valve. The second flow circuit includes the aforesaid reservoir, a second pump connected to the reservoir through a second inlet conduit and a second return conduit, a second fluid motor for the radiator cooling fan in the second return conduit, and a second flow control valve. Fluid in the first return conduit is conducted into the reservoir substantially without turbulence. Fluid in the second return conduit is conducted into the reservoir as a jet stream aimed at a submerged passage in a venturi tube. The submerged passage communicates with a feeder conduit between the reservoir and each of the first and the second inlet conduits.