Part # 5250-225

Manufacturer Code PS-3865

Dimensions 0.8" x 1.25"

Alternate Part #'s 319-3100B, PS-1000, PS-3865, PS-3865R, PS1000, PS3865, PS3865R, 35-423-1048, APCPS3865R, PSR-1000V, PSR1000V, USSPS3865R

Product Description

Heavy duty pump motor shaft seal made with carbon graphite, stainless steel and Viton rubber.  These materials provide increased durability and resistance to chemicals and salt.  

Commonly Used In

  • Pentair Whisperflo Pump
  • Polaris Booster Pump (1994-2011)
  • Pentair Letro Booster Pump (1997-Current)
  • Waterway SMF Pump
  • Waterway SVL56 High Flow Pump
  • Waterway Hi-Flo Pump
  • American Products Ultra-Flo

Can be used for standard chlorine pools.  Strongly recommended for use on pool and spa pumps connected to salt chlorine systems or ozonators.

This seal can be used on a number different makes and models of pumps (see complete list under the "Parts" tab above).  Some of the more common pumps include the Pentair Whisperflo, American Products Ultra Flo, Polaris PB460 booster pump, and Astral Astra Max.

Frequently Bought with this Shaft Seal

Clear RTV Silicone 6558-0 (For gluing shaft seal into the seal plate)

Shaft Seal, PS-1905, 5/8" Shaft, Silicon Carbide PS-1000 is available PART # PS-1905 Click here https://www.inyopools.com/Products/24201352088384.htm  to view for ordering 


?     Asked on 1/17/2012by Guest

Why should I purchase the heavy duty seal?

A  Answered on 1/17/2012 by InyoPools Product Specialist Patrick P.

The heavy duty shaft seal features carbon graphite, stainless steel, and Viton rubber. The properties of this seal contribute to the resistance of chemical corrosion. This is the best choice for salt chlorine generators or ozonators.

?     Asked on 1/25/2012by Guest

How do I change the shaft seal on my pool pump?

A  Answered on 1/25/2012 by InyoPools Product Specialist Patrick P.

Changing the shaft seal is quite simple. Here's How To Replace a Pool Motor Shaft Seal.

?     Asked on 12/10/2014by Wayne Gill

Is this the correct seal for a Polaris PB4-60W

A  Answered on 12/10/2014 by InyoPools Product Specialist Alex V.

Wayne, Yes. This can be used on the Polaris PB4-60 booster pump.

?     Asked on 6/4/2016by Inyo Visitor

how is this part replaced

A  Answered on 6/5/2016 by InyoPools Product Specialist Patrick P.

We have a Video on How to Replace a Pool Pump Shaft Seal which you should find helpful.

?     Asked on 1/18/2018by Julie

Pump Seal 1000, Heavy Duty PS3865 (Saltwater Pools) - PS-3865 Is this the correct seal for Polaris Whisper 011772?

A  Answered on 1/18/2018 by InyoPools Product Specialist Lennox H.

Hi, Julie. This Pump Seal will fit the Pentair Whisperflo Pump - 011772. 


Est. Repair Time

Less than 1 hr

Tools Needed

Socket Set

1     0

Bearings on pump went bad.

Written on 6/1/2020 by Guest

After removing pump, followed directions on INYO pool video for pump replacement. I ordered the heavy duty seal since the previous pump/seal might have failed and that was the reason for the bearings going bad. Did water get in? I don't know, but thought for the few extra $$ a heavy duty seal would be a better choice. Got old seal out of Faceplate using socket the fit the diameter of the seal. Used a rubber hammer to remove. Installed new seal in the same manner. USE A RUBBER HAMMER TO PREVENT DAMAGE TO SEAL.

Were these instructions helpful? 


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