PYI PSS Type A Shaft Seal, 2-1/2" Shaft / 4" Tube – ABS Certified

Upgrade your vessel's propulsion system with the PYI PSS Type A Shaft Seal, the world's leading marine mechanical seal designed to deliver a 100% watertight seal and eliminate propeller shaft wear. This dripless solution is engineered for 2-1/2" shafts and 4" stern tubes, significantly reducing bilge water and maintenance associated with traditional packing glands. Proudly manufactured in the USA and trusted by top boat builders globally, it is certified by Bureau Veritas, ABS, RINA, and US Coast Guard approved, ensuring unparalleled reliability and performance. Invest in superior marine engineering for peace of mind on every voyage.

Key Features & Benefits:

• Dripless Operation: Provides a 100% watertight seal, effectively eliminating bilge water and protecting your vessel's interior.
• Reduced Maintenance: Replaces traditional packing glands, eliminating the need for constant adjustment and preventing wear to the propeller shaft.
• Robust Construction: Features a rotating 316L stainless steel rotor and a stationary high-density, resin-impregnated carbon graphite flange.
• Misalignment & Vibration Compensation: The carbon flange is bored larger than the shaft diameter, allowing it to "float" and compensate for most shaft misalignment and vibration issues.
• Broad Compatibility: Designed for 2-1/2" shaft diameters and 4" stern tube diameters, with the PSS system available for a wide range of shaft sizes from 3/4" (20mm) to 6" (150mm).
• High Thermal Resistance: The carbon flange has an operating temperature exceeding 500°F (260°C), preventing melting even if the seal runs dry. The Nitrile rubber bellows have a temperature rating of -25°F to +225°F (-31°C to +107°C).
• Durable Bellows: Constructed from molded Nitrile rubber, known for its resistance to weathering, oils, non-polar solvents, and good abrasion resistance.
• Impressive Performance Limits: Capable of handling pressure limits up to 15 PSI (1 BAR) and shaft RPMs up to 10,000 RPM.
• Certified Quality: Approved by leading maritime classification societies including Bureau Veritas, ABS, and RINA, along with US Coast Guard approval.
• Optimal Dimensions: Uncompressed total length of 9.625" (compressed length of 8.375"), rotor diameter of 4.2", carbon cuff diameter of 3.75", and stern cuff length of 2".

Maintenance Recommendation: For optimal performance, the PSS bellows should be inspected regularly and replaced every six years. During bellows replacement, it is also recommended to replace the O-rings, set screws, and hose clamps.