NAPCO pump gears are pressure-fitted on to the shafts. Because most NAPCO customers lack the equipment to pull off and press a new gear on an existing pump shaft, NAPCO offers its customers drive gear and idler gear “assemblies” with the gear already mounted on the appropriate shaft. These assemblies are included in the NAPCO Spare Parts Kit, but the customer may also order them separately. Please identify the appropriate gear assembly and part number from the following list:
| Identification Number | Description |
| 2” ductile iron or stainless steel pump (PA200C or PA200S) | |
| PA250C | 2” ductile iron drive shaft with mounted nitrile gear |
| PA250S | 2” stainless steel drive shaft with mounted nitrile gear |
| PA251C | 2” ductile iron idler shaft with mounted nitrile gear |
| PA251S | 2” stainless steel idler shaft with mounted nitrile gear |
| 3” ductile iron or stainless steel pump (PA300C or PA300S) | |
| PA350C | 3” ductile iron drive shaft with mounted nitrile gear |
| PA350S | 3” stainless steel drive shaft with mounted nitrile gear |
| PA351C | 3” ductile iron idler shaft with mounted nitrile gear |
| PA351S | 3” stainless steel idler shaft with mounted nitrile gear |