a clamping and seal loading technique for securing the plunger sleeve to the pump housing of a single plunger fuel pump . this is achieved by providing a load ring between a sleeve retainer and the sleeve , such that the axial force applied by the retainer during installation and attachment to the plunger bore wall of the housing , is distributed more evenly on the sleeve and the sealing surface of the sleeve against the housing adjacent to the pumping chamber . the even distribution of force minimizes misalignment of the sleeve and thus maintains concentricity between the sleeve and the plunger .