The Bison Pumps come with a Lifetime Warranty on the stainless-steel parts and construction. However, you may still need to perform maintenance on your pump. Maintenance is rarely required beyond winterization, but some situations can cause excessive wear or damage to consumable pump components.
Cup Seals and O-Ring:
If used normally, these seals will last many years. The wear to these seals is directly related to the amount of pumping and the condition of the water. If your water has contaminants they could act as an abrasive and cause wear to the packing gland, piston cup seals and O-rings.
f you’re in a situation of high use AND low-quality water, the sealing components may need to be replaced eventually. For this, you can call and order the Bison Pumps Seal Maintenance Kit (https://www.bisonpumps.com/product/repair-kit/). The kit has everything you need to repair your pump.
The Bison Pumps Seal Maintenance Kit includes:
- 1x Gland Nut
- 1 x Plastic Packing Gland Washer
- 1 x ½” x 1” Packing Gland Cup Seal
- 1 x Top Plate O-ring
- 1 x Bottom Bushing
- 2 x Piston Cup Seal
- 1 x Spring Pin
- 1 x Seal Pick Tool
Bison Tip: While you’re got your pump disconnected, take advantage of this time and clean the inside components of the pump. It’s best to first remove the components that will be replaced and THEN clean the inside of the pump. Finally, install the new components. While it’s out, inspect the Check Valve in the bottom of the Piston and Check Valve Housing. Make sure it’s clear of any debris that might prevent the Check Valve from closing properly. Given proper care, the Check Valve should last a lifetime. However, if the Check Valve is damaged by large debris, call Bison Pumps for a replacement. 1-800-339-2601.
Source : https://www.bisonpumps.com/maintenance-on-the-bison-model-1900-shallow-well-hand-pump/