Polaris PB4-50 Booster Pump Bracket Adaptor O-Ring (WS0137300)

Genuine Polaris PB4-50 Booster Pump Bracket Adaptor O-Ring — part no. WS0137300. This is the large rubber O-ring (item 3 in the PB4-50 exploded diagram) that seals the volute (pump body) to the bracket adaptor plate on the Polaris PB4-50 booster pump. A worn or cracked O-ring causes water to leak from the joint between the volute and the bracket adaptor. Replacing this O-ring restores a watertight seal.

Compatibility

• Polaris PB4-50 Booster Pump — 2011 to current (new style)

Product Details

• Brand: Polaris / Zodiac
• Part number / SKU: WS0137300
• Position: item 3 in PB4-50 exploded diagram (volute / bracket adaptor O-ring)
• Genuine Polaris spare part

Frequently Asked Questions

How do I know if this O-ring needs replacing?

If water is leaking from the joint between the pump volute (the front pump body) and the bracket adaptor plate, this O-ring is the most likely cause. Turn off the pump and relieve system pressure before inspecting. Remove the volute bolts, separate the volute from the bracket adaptor, and inspect the O-ring for cracks, flattening, or deformation. Replace if any damage or deterioration is visible.

Does this suit the older PB4-60 or pre-2011 PB4-50?

Part WS0137300 suits the PB4-50 from 2011 to current (new style). Pre-2011 PB4-50 and PB4-60 models may use a different O-ring. If you are unsure of your pump’s manufacture date, check the label on the pump body or contact us with your pump’s serial number before ordering.

Should I lubricate the O-ring when fitting it?

Yes — apply a small amount of silicone-based O-ring lubricant (not petroleum-based grease) to the O-ring before fitting. This helps the O-ring seat correctly and extends its service life.