Fuel injection pump

A fuel injection pump of the multiple plunger spill port type for an automotive type internal combustion engine, the pump including a housing having a central cavity therein receiving a rotatable engine driven camshaft, a pair of axially spaced stationary pump plunger bores each projecting radially through the housing from the camshaft and each reciprocably mounting a plunger engageable with the camshaft for movement thereby upwardly through a fuel pumping stroke and downwardly through a fuel intake stroke, each bore defining a fuel chamber contiguous to the plunger end opposite to that engaged by the camshaft, each bore having a fuel inlet/spill passage through the wall of the bore contiguous to each chamber for the supply of fuel to and the spill of fuel therefrom, a fuel discharge passage containing fuel pressure responsive means therein connecting each of the chambers individually to an engine cylinder, a source of low pressure fuel, fuel supply lines connecting the source to each of the fill/spill passages and fuel chambers, a low pressure fuel return line, a spill port in the line connected in parallel fuel flow relationship to each of the fill/spill passages, and spill port fuel flow control valve means moveably associated with the supply and return lines to block or permit flow therethrough to control the pressurization of fuel in one of the fuel chambers and its discharge line while supplying fuel at low pressure to another of the chambers, and vice versa, the valve means including a single spill control valve movable to block or unblock the spill port, electromagnetic means energizable to move the spill valve to a spill port blocking position, and a shuttle valve reciprocably movable between a first position connecting one of the pair of fill/spill passages to the supply line and source and the other of the pair of fill/spill passages to the spill port and return line, and vice versa for a second position, the shuttle valve being fuel pressure movable to its reciprocable positions as a function of the pumping movement of the respective plungers associated therewith directing fuel against various opposite portions of the shuttle valve.