Sta-Rite Extended Tooth Lock Washer, U43-21SS

The Sta-Rite U43-21SS is the extended tooth lock washer used through the Sta-Rite pump line. It is the genuine factory part, the one the manufacturer parts breakdowns call out by number.

Where it turns up

This washer is not tied to one pump. It is listed for the Dyna-Pro and Dyna-Pro E, Max-E-Pro, Max-E-Glas and Dura-Glas, Max-E-Glas II and Dura-Glas II, Dyna-Glas and Dyna-Max, and the IntelliPro VS 3050, and it carries across to Pentair as well, showing up in the Pinnacle, Dyna-Wave and IntelliPro variable speed parts lists.

Why bother replacing it

An extended tooth washer grips because its teeth deform against the fastener and the surface below. Once it has been torqued down and backed off, most of that spring is gone. Reusing one is a common shortcut and a common reason hardware works loose again a season later. If you have the pump apart, put fresh washers back in.

Before you order

Open the parts breakdown for your pump and confirm the position and the count. Several assemblies on the same pump can call for this washer, so it is easy to come up one short.