Abstract

Apparatus for adjustment of the main metering jet of a modular type high performance engine carburetor avoiding the problem of having to partially disassemble the carburetor in order to change the main metering jets. The invention includes a continuously adjustable elongated metering rod having a tapering point proximate the fuel orifice hole of an elongated cylindrical fuel metering jet, the rod adapted to pass horizontally through the carburetor float bowl module to the outside of the carburetor for external adjustment. The main metering jet is modified by a transverse located opening to pass fuel to the longitudinal fuel orifice hole with a second larger diameter concentric longitudinal hole adapted to receive and guide the metering rod pointed end into the fuel orifice hole. The metering rod passing through the wall of the float bowl module is rendered liquid-tight by means of closely threaded internal threads on an inside bushing mating with external threads on the metering rod, and an O-ring between the head of the bushing and the wall of the float bowl module with a nut screwed onto the external threads of the bushing shank exteriorly to the float bowl module. The metering rod presents a screwdriver slot for manual rotational fuel adjustment.