Abstract: A locking device for securing a packing nut on a fracking pump is disclosed. The locking device includes a clamp secured to the packing nut and a stop arm that rests on a fixed rod (e.g., a stay rod) of the fracking pump. With the clamp secured to the packing nut and the stop arm contacting and resting on the stay rod, the packing nut is inhibited from loosening or disengaging from a cylinder block of the fracking pump.

Abstract: A system for automatically filling a fuel tank coupled to a fracking pump is described. The filling system includes a device that automatically opens and closes fuel flow to the fuel tank based on a level of fuel in the fuel tank. The device may close fuel flow to the fuel tank when a fill capacity of the fuel tank is reached. The device may open fuel flow to the fuel tank when a fuel level in the fuel tank drops below a selected level (e.g., below 1/4 of the fill capacity of the fuel tank). The device may be used to substantially continuously supply fuel to the fuel tank.