A gravitational pressure regulating mechanism for use with a valve is provided for control of pressure and diversion of bodily fluids. The mechanism includes a reservoir having first and second ends, the first end being open and the second end having a floor and an entry port, and a free floating weight adapted to freely slide in the reservoir from a closed position wherein the weight is adjacent the floor to an opened position wherein the weight is positioned away from the floor. The weight has a closure member having a surface to engage the entry port when the weight is in the closed position. The mechanism further includes a cap having an exit port to seal the open first end of the reservoir. The mass of the weight is proportional to the amount of resistance to flow of the bodily fluids through the regulating mechanism.