A jet pump assembly comprising: a unitary nozzle carrier having a wall with a first entrance port; wherein the nozzle carrier has a longitudinal passage extending through the nozzle carrier and in fluid communication with the first entrance port; wherein the wall has an additional entrance port (50A, 50B, 50C) extending through the nozzle carrier in fluid communication with the longitudinal passage, and spaced angularly from the first entrance port; a unitary venturi nozzle having an inlet and a nozzle tip forming an outlet; wherein the venturi nozzle is configured to fit to the nozzle carrier at a controlled radial clearance in the longitudinal passage so that alignment of a longitudinal axis of the nozzle with a longitudinal axis of the venturi nozzle is affected only by the fit of the nozzle carrier to the venturi nozzle; wherein the nozzle tip extends past the first entrance port and is in fluid communication with the entrance port when the venturi nozzle is fit to the nozzle carrier; in combination with a housing forming a liquid trap and an end cap closing one end of the housing; wherein the entrance port is in operative fluid communication with the liquid trap; characterized in that: the venturi nozzle has a first stepped shoulder configured to abut an outer end surface of the nozzle carrier when the venturi nozzle is fit to the carrier portion in the longitudinal passage so that a predetermined radial clearance exists between the nozzle tip and the nozzle carrier; wherein the diffuser portion is supported by the housing and the carrier portion is supported by the end cap; and wherein a radial clearance between the first stepped portion of the venturi nozzle and the end cap is greater than the controlled radial clearance. a unitary nozzle carrier having a wall with a first entrance port; wherein the nozzle carrier has a longitudinal passage extending through the nozzle carrier and in fluid communication with the first entrance port; wherein the wall has an additional entrance port (50A, 50B, 50C) extending through the nozzle carrier in fluid communication with the longitudinal passage, and spaced angularly from the first entrance port; a unitary venturi nozzle having an inlet and a nozzle tip forming an outlet; wherein the venturi nozzle is configured to fit to the nozzle carrier at a controlled radial clearance in the longitudinal passage so that alignment of a longitudinal axis of the nozzle with a longitudinal axis of the venturi nozzle is affected only by the fit of the nozzle carrier to the venturi nozzle; wherein the nozzle tip extends past the first entrance port and is in fluid communication with the entrance port when the venturi nozzle is fit to the nozzle carrier; in combination with a housing forming a liquid trap and an end cap closing one end of the housing; wherein the entrance port is in operative fluid communication with the liquid trap; characterized in that: the venturi nozzle has a first stepped shoulder configured to abut an outer end surface of the nozzle carrier when the venturi nozzle is fit to the carrier portion in the longitudinal passage so that a predetermined radial clearance exists between the nozzle tip and the nozzle carrier; wherein the diffuser portion is supported by the housing and the carrier portion is supported by the end cap; and wherein a radial clearance between the first stepped portion of the venturi nozzle and the end cap is greater than the controlled radial clearance. the venturi nozzle has a first stepped shoulder configured to abut an outer end surface of the nozzle carrier when the venturi nozzle is fit to the carrier portion in the longitudinal passage so that a predetermined radial clearance exists between the nozzle tip and the nozzle carrier; wherein the diffuser portion is supported by the housing and the carrier portion is supported by the end cap; and wherein a radial clearance between the first stepped portion of the venturi nozzle and the end cap is greater than the controlled radial clearance.