System, method and apparatus for controlling fluid flow through drill string

A downhole tool system for a well, comprising:

• a drill pipe having an axis;
• a mud motor coupled to the drill pipe;
• a drill bit coupled to the mud motor;
• a housing coupled to the drill pipe uphole from the mud motor, the housing having an axis, a radial wall with a bore extending axially through the radial wall, and an aperture formed in the radial wall, the aperture being in fluid communication with the bore and an annulus between the drill pipe and the well;
• a component located inside the housing and having an orifice configured to permit downhole axial fluid flow through the housing;
• a bias device located in the housing, the bias device being configured to bias the component to a closed position;
• and
• the component is configured to be movable from the closed position wherein the component is configured to substantially close the aperture in the housing to substantially block fluid flow therethrough when downhole axial fluid flow through the orifice is insufficient to overcome a bias of the bias device, and an open position wherein the component is configured to permit fluid flow through the aperture when downhole axial fluid flow through the orifice is sufficient to overcome the bias of the bias device and move the component.