Abstract: A reciprocating assembly includes a bore that contains hydraulic fluid. A piston is received within the bore and can move within the bore in a reciprocating motion between an extended position and a retracted position. Displacement of the piston within the bore causes displacement of hydraulic fluid when hydraulic fluid is in the bore. The piston includes an internal cavity extending at least partially along a length of the piston. The reciprocating assembly also includes a push pin that is received within the internal cavity. The bore, piston, and push pin are arranged so that movement of the push pin related to the bore causes translation of the piston within the bore to the extended position along a translation axis. The push pin can pivot during movement of the push pin between an in-line position and an angled position. The in-line position is substantially parallel to the translation axis.