Abstract: Apparatus, for metering a predetermined amount of fuel for injection into a combustion engine, having a plunger slidable within a metering chamber wherein fuel is drawn into the metering chamber when the plunger is withdrawn from the chamber to an outer position and fuel is pumped from the metering chamber into the combustion engine when the plunger is forced into the metering chamber to an innermost position. An adjustable governor is provided for variably limiting the degree of withdrawal of the plunger from the metering chamber to regulate the metered amount of fuel. A rotating cam driven by the combustion engine normally maintains the plunger at its innermost position within the metering chamber to permit free adjustment of the governor and permits withdrawal of the plunger to allow the metering chamber to fill with fuel only immediately prior to the pumping stroke wherein the plunger is forced into the chamber causing the metered fuel to enter the combustion engine.