The invention relates to an apparatus and method of statically sealing a
reciprocating-type fuel pump, such as a direct injection high pressure
piston-type fuel pump. The first embodiment of the invention is a fuel
pump comprising a pump body, a fuel reservoir within the pump body,
wherein the fuel reservoir is capable of holding fuel and a bellows
attached to the pump body, wherein the bellows is a stretchable membrane
acting as a static seal. The second embodiment further comprises a
diaphragm seal inside the pump body, and adjacent to the fuel reservoir,
and a working fluid reservoir adjacent to the diaphragm seal, wherein the
working fluid reservoir is capable of holding fluid. The diaphragm seal
is a static seal separating the working fluid reservoir and the fuel
reservoir.