SKU: 42074210986

PSS PRO Shaft Seal 2-3/4" Shaft 4" Tube

Sale price$488.16 Regular price$542.40
Save 10%

Pay in installments of $135.60 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Aug 25 - Aug 30

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

PSS PRO Shaft Seal 2-3/4" Shaft 4" TubePRO Shaft Seal 2 3 4" Shaft & 4" Tube The PSS PRO Shaft Seal is a mechanical face seal utilizing PSS Shaft Seal's proven stainless steel and carbon sealing components but adding reinforced silicone bellows, a secondary shaft retention collar, 316 stainless steel hose clamps (rolled edges and non perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased

PRO Shaft Seal 2-3/4" Shaft & 4" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing PSS Shaft Seal's proven stainless steel and carbon sealing components but adding reinforced silicone bellows, a secondary shaft retention collar, 316 stainless steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high-pressure, and otherwise demanding environments, the PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications with unmatched performance.

As with PSS Type A & B Seals, the PRO 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 a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log) with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows. The rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial 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 from the drive line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Components:

Shaft Retention Collar

The PYI Shaft Retention Collar is designed to help retain the propeller or rudder shaft in a vessel in the event of catastrophic failure of the coupling or if the shaft comes free from the coupling. The double-split design provides maximum axial holding power with quick and efficient assembly with the shaft installed. The design fully engages the shaft without marring. Easily installed where major disassembly would otherwise be required. Greater axial holding power than set screws or one-piece clamping collars. Effective on hard and soft shafts.

Rotor

The rotor on the PRO seal is manufactured out of 316L stainless steel and machined to a 9–12Ra finish on precision CNC lathes. It is secured on the shaft using 2 pairs of set screws positioned at a 90-degree angle; in addition, a locking collar is placed in front of the rotor and further retains the propeller or rudder shaft in case of catastrophic failure of the coupling or if the shaft comes free from the coupling. As on the Type A seal, the stainless steel rotor further polishes the carbon stator during the initial hours of operation.

Carbon Stator

The high-density resin-impregnated carbon stator is manufactured from an advanced composite that is first mixed, molded, and then formed under pressure. The blank parts are then baked, machined, and lapped to a measured flatness of 4 helium light bands (measured at 0.000044" of variation over its entire lapped surface). The grade of carbon composite used in the PSS Shaft Seal has a maximum operating temperature of 500 °F (+260 °C) and cannot melt if the seal runs dry for a short period, unlike a lip seal or a plastic face seal. In addition, the high density of the carbon greatly increases longevity and wear resistance. Several commercial vessels have recorded over 40,000 (over 4-1/2 years of continuous operation) engine hours on the same original components.

Bellows

The bellows on both the PRO and Type B PSS seals are constructed out of high-temperature silicone laminated with either 4 or 5 plies of polyester fabric (aramid in larger sizes) and covered with a layer of fluorosilicone. In addition, both ends of the bellows are sealed so no water can get into the polyester/Aramid fabric. The 4 or 5 fabric inlay provides excellent strength to abrasion and resistance to pressure without loading the silicone. On the larger models, the strength is greatly increased by using stainless steel hoops laid into the convolutions of the bellows.

Hose Barb

For high-speed vessels (planning hulls or vessels powering over 12 knots), it is required that a positive water supply be plumbed to the PSS Shaft Seal for lubricating and cooling the seal faces. There are many water supply sources; review the PSS Shaft Seal Installation Instructions for more information and note that all plumbing must follow the standards and practices of proper boat plumbing. In most cases, a slow-speed boat with no bearing in the shaft log does not require positive water feed and can be "vented." Ideally, the vent line will be run at least 2-3 feet above the waterline and as close to the centerline as possible to ensure the vent hose is never below the water line, even if the boat heels. Again, review the PSS Shaft Seal Installation Instructions for more details on venting the seal.

Specifications:

  • Temperature Limits: -13°F to 425°F (-25°C to 220°C)
  • Pressure Limits: 40 PSI (2.75 BAR)
  • Shaft RPM Limits: 10,000 RPM
  • Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
  • 316SS / Nitronic 50: Faced to 9 Ra
  • Bellow Material: Molded formed silicone/fabric

Product Dimensions:

  • Shaft Diameter: 2-3/4"
  • Stern Tube Diameter: 4" to 4-1/8"
  • Uncompressed Length: 9.988"
  • Approx. Compressed Length: 8.988"
  • Rotor Diameter: 5"
  • Stern Cuff Length: 1.3"
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 42074210986

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.2 ★★★★★
Based on 27 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
A
Verified Purchase
amir elbanna
Natrona Heights, US
★★★★★ 5
Very insightful
Format: Paperback
A very interesting way to break down the concepts of basic and/or sophisticated cybersecurity. In that retrospect, you come to see that all security measures are quite the same. The difference lies in the environment; one is a corporate office, the other is Feudal Japan. It's a good read
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 6, 2025
J
Verified Purchase
John
Alexandria, US
★★★★★ 5
Great book
Format: Paperback
Worth the buy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 8, 2022
A
Verified Purchase
Amazon Customer
Grantham, US
★★★★★ 1
Do not waste your time
Format: Paperback
Just saying the same things as other authors and trying to make it unique. If you want consistency with industry avoid this book.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on August 9, 2022
K
Verified Purchase
Kimberly Grant-Flythe
Houston, US
★★★★★ 5
wow “Why” had I not seen this sooner
Format: Kindle
I have encountered and read may of T D Jake’s books before but none that before I could even get to the first chapter had me totally hooked that I had to sit it down and think and jot down thoughts. This book even though small is profound, and biblically sound in directing not only the believer but the anointed believer to the throne of GOD . I know I’m going to read it again many times . Thank you Increasing Faith School of Christian Education for recommending.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 28, 2026
G
Verified Purchase
Gloria J Jones
Port Orchard, US
★★★★★ 5
Testimony
Format: Paperback
Awesome reading
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 25, 2026

recommand products