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PSS Shaft Seal Selector
PSS Shaft Seals

PSS Shaft Seals

Complete mechanical seal for marine applications

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PSS Maintenance Kits

PSS Maintenance Kits

Maintenance Kits for the PSS Shaft Seal

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PSS Accessories

PSS Accessories

Numerous accessories or replacement components for the PSS Shaft Seal

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PSS Shaft Seals

#1 Selling Shaft Seal Worldwide

The PSS Shaft Seal is the #1 selling marine mechanical seal worldwide and is installed as standard equipment by many of the world's most reputable boat builders and boatyards. The PSS Shaft Seal is also recognized as the premiere retrofit (aftermarket) seal on the world market. Boatbuilders and boat yards recognize the advantages and value of installing the PSS as it eliminates the maintenance, constant adjustment, and cost associated with a traditional type of packing glands. Aside from these benefits, the PSS Shaft Seal helps to eliminate water in the bilge (100% watertight) and wear to the propeller shaft. Any vessel can easily be retrofitted with a PSS Shaft Seal and is available for shafts ranging from 3/4” to 6-1/2” (20mm to 150mm).

How Does It Work

The PSS Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to the front side of the bellows with hose clamps, and the back end of the bellows fits over the stern tube and is secured with hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange. The stainless-steel rotor compresses the bellows before the rotor is secured to the shaft with set screws. This compression (pre-load) maintains constant contact between the two flat faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable fore and aft movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to float around the shaft and thus compensate for most misalignment and vibration problems. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the collar's bore. These O-rings rotate with the shaft and stainless-steel rotor and do not experience wear during operation.

How a PSS Seal works

PSS Shaft Seal Components

Click or hover over the components to see more information.

stainless steel rotor
carbon stator
rubber bellows


The PSS Shaft Seal has been thoroughly tested and approved by these certifications.

ABS Certification


What Is A PSS Shaft Seal Video

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Contact Us

  • U.S. Headquarters
  • 12532 Beverly Park Road, Ste. B
  • Lynnwood, WA 98087
  • Tel: 425-355-3669
  • Toll Free: 800-523-7558
  • Fax: 425-355-3661
  • Office Hours:
  • Monday - Friday, 7:00am - 4:00pm PST
  • European Headquarters
  • Zl du Capitou, 85 rue Louis Lepine,
  • 83600 Frejus - France
  • Tel: +33 4 94 53 27 70
  • Fax: +33 4 94 53 26 62
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