Most centrifugal pumps today have mechanical seals. However, those pumps that still use packing glands instead of mechanical seals require frequent maintenance and are more likely to show up in the service center for repair. The average mean time between failure (MTBF) for mechanical seals is about 7500 hours. Packing glands require packing replacement after about 1,000 hours of operation. And the shaft or shaft sleeve for packing gland pumps is subject to wear, so pump overhaul to repair the shaft or replace the sleeve is inevitable. Improper installation or adjustment of packing glands can greatly accelerate wear, making much more frequent repair necessary. Replacing packing is not a technically demanding task. However, there are some tips that will improve the performance of the packing, limit the energy usage and extend the MTBF. Attention to these details will allow service centers to provide quality repairs for their customers.