Pentair U43-12SS split lock washerPentair Split Lock Washer, U43-12SS$1099
Pentair U43-12SS split lock washer
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Pentair Split Lock Washer, U43-12SS

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$1099
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Quick overview

  • Genuine Pentair part Factory split lock washer U43-12SS.
  • Split ring design The gap in the ring springs against the fastener so it resists working loose.
  • Listed for XF pumps Shown on the WhisperFlo XF and on the IntelliFlo XF VSF and IntelliFlo XF VS parts diagrams.
  • For pumps built after August 2015 That is the range the IntelliFlo XF diagram covers.
  • Vibration is the enemy A running pump shakes fasteners loose, which is exactly what a lock washer prevents.
  • Replace corroded hardware A washer that has lost its spring no longer locks anything.
Full description and specifications ↓

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Product details

The Pentair U43-12SS is a split lock washer used in Pentair pump assemblies. It is the genuine Pentair part.

Where it appears

Pentair lists it on the WhisperFlo XF parts diagram and on the IntelliFlo XF VSF and IntelliFlo XF VS diagram covering units manufactured after August 2015.

What it does

A split lock washer is a sprung ring with a gap in it. Tightening the fastener compresses the ring, and the spring load it stores is what keeps the fastener from vibrating loose on a running pump. Once the washer has corroded or been flattened permanently, it has no spring left and is doing nothing, so it should be replaced rather than reused.

Specifications
Brand Pentair
Manufacturer part number U43-12SS
UPC 788379773120
Type Split lock washer
Shown on Pentair WhisperFlo XF pump parts diagram; Pentair IntelliFlo XF VSF and IntelliFlo XF VS pump parts diagram, manufactured after August 2015
Shipping weight 0.05 lb
Ships Parcel

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Questions and answers

What people ask about this product, answered by our pool techs.

Which pumps is this washer listed for?
It appears on the Pentair WhisperFlo XF parts diagram and on the IntelliFlo XF VSF and IntelliFlo XF VS diagram for units manufactured after August 2015.
What does a split lock washer do?
The split ring is sprung. When the fastener is tightened the washer compresses and pushes back, which is what keeps the fastener from backing off as the pump vibrates.
Can I reuse the old one?
Not if it has lost its spring or is corroded. A flattened lock washer is just a flat washer and no longer does its job.
Is there more detail available on this part?
The source listing is minimal beyond the part number and the diagrams it appears on. If you need a specific bolt size, check the diagram position against your pump before ordering.
Ask your own question