A pump comprising: a casing defining an interior volume, the casing including a first port in fluid communication with the interior volume, and a second port in fluid communication with the interior volume; a first gear disposed within the interior volume, the first gear having a first gear body and a plurality of first gear teeth; a second gear disposed within the interior volume, the second gear having a second gear body and a plurality of second gear teeth projecting radially outwardly from the second gear body, the second gear is disposed such that a second face of at least one tooth of the plurality of second gear teeth aligns with a first face of at least one tooth of the plurality of first gear teeth; a first motor that rotates the first gear about a first axial centerline of the first gear in a first direction to transfer a fluid from the first port to the second port along a first flow path; a second motor that rotates the second gear, independently of the first motor, about a second axial centerline of the second gear in a second direction to contact the second face with the first face and to transfer the fluid from the first port to the second port along a second flow path; and at least one flow-through shaft (42,62), wherein: the at least one flow-through shaft (42,62) is disposed in at least one of the first motor, the second motor, the first gear and the second gear, each of the at least one flow-through shaft (42,62) having a through passage (184,194) along an axial centerline of the respective flow-through shaft (42,62) such that a first end of the through-passage (184,194) is configured to be in fluid communication with a fluid chamber of a storage device and a second end of the through-passage (184,194) is configured to be in fluid communication with the first port or the second port, the fluid is a hydraulic fluid or water, each through-passage (184, 194) of the at least one flow-through shaft (42, 62) comprises a tapered portion extending from the first end of the through-passage (184, 194) and to a point part-way into the through-passage (184, 194), and a diameter of the tapered portion at the first end of the through-passage (184, 194) is larger than a diameter of the tapered portion at the point part-way into the through passage (184, 194) a casing defining an interior volume, the casing including a first port in fluid communication with the interior volume, and a second port in fluid communication with the interior volume; a first gear disposed within the interior volume, the first gear having a first gear body and a plurality of first gear teeth; a second gear disposed within the interior volume, the second gear having a second gear body and a plurality of second gear teeth projecting radially outwardly from the second gear body, the second gear is disposed such that a second face of at least one tooth of the plurality of second gear teeth aligns with a first face of at least one tooth of the plurality of first gear teeth; a first motor that rotates the first gear about a first axial centerline of the first gear in a first direction to transfer a fluid from the first port to the second port along a first flow path; a second motor that rotates the second gear, independently of the first motor, about a second axial centerline of the second gear in a second direction to contact the second face with the first face and to transfer the fluid from the first port to the second port along a second flow path; and at least one flow-through shaft (42,62), wherein: the at least one flow-through shaft (42,62) is disposed in at least one of the first motor, the second motor, the first gear and the second gear, each of the at least one flow-through shaft (42,62) having a through passage (184,194) along an axial centerline of the respective flow-through shaft (42,62) such that a first end of the through-passage (184,194) is configured to be in fluid communication with a fluid chamber of a storage device and a second end of the through-passage (184,194) is configured to be in fluid communication with the first port or the second port, the fluid is a hydraulic fluid or water, each through-passage (184, 194) of the at least one flow-through shaft (42, 62) comprises a tapered portion extending from the first end of the through-passage (184, 194) and to a point part-way into the through-passage (184, 194), and a diameter of the tapered portion at the first end of the through-passage (184, 194) is larger than a diameter of the tapered portion at the point part-way into the through passage (184, 194) the at least one flow-through shaft (42,62) is disposed in at least one of the first motor, the second motor, the first gear and the second gear, each of the at least one flow-through shaft (42,62) having a through passage (184,194) along an axial centerline of the respective flow-through shaft (42,62) such that a first end of the through-passage (184,194) is configured to be in fluid communication with a fluid chamber of a storage device and a second end of the through-passage (184,194) is configured to be in fluid communication with the first port or the second port, the fluid is a hydraulic fluid or water, each through-passage (184, 194) of the at least one flow-through shaft (42, 62) comprises a tapered portion extending from the first end of the through-passage (184, 194) and to a point part-way into the through-passage (184, 194), and a diameter of the tapered portion at the first end of the through-passage (184, 194) is larger than a diameter of the tapered portion at the point part-way into the through passage (184, 194)