Patent ID: 7523722

Claim:
A safe, reliable system for automatically dosing fuel tanks with a fuel additive, particularly a concentrate containing a fuel borne catalyst (FBC) for increasing fuel economy and/or lower emissions using gravity as the means of injection on the basis of a signal from a switch located on the fuel tank filler spout and is actuated by removal of the filler cap, comprising: a supply vessel for fuel borne catalyst concentrate positioned at a predetermined height above a fuel tank for holding fuel to power a diesel engine; a fuel tank filler spout leading to the fuel tank and including a reed switch; a removable cap for the fuel tank filler spout including magnets capable of operating the reed switch on said filler spout; a supply line which permits fuel borne catalyst concentrate to flow from the supply vessel to the fuel tank; an actuator operated dispensing valve positioned in the supply line; wherein when the cap is removed from the fuel tank filler spout, the reed switch causes the dispensing valve to open and for fuel borne catalyst concentrate to flow by gravity from the supply vessel through the valve and to the fuel tank.