Shaft Seal 45mm Shaft & 3-1/4" Tube This Type A 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 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 boat yards. The PSS Shaft Seal is also recognized as the premiere retrofit (aftermarket) seal on the world market. Boat builders and boat yards recognize the advantages and value of installing the PSS, as it eliminates the maintenance, constant adjustment, and cost associated with traditional packing-type glands. Aside from these benefits, the PSS Shaft Seal helps to eliminate water in the bilge (100% watertight) and wear to the propeller shaft.  How Does it Work? Two nitrile o-rings seal the stainless steel rotor to the shaft and will not experience wear. A primary set screw and a backup set screw (2 sets) are used to secure the stainless steel rotor to the shaft. A seal is created between the two flat surfaces of the carbon stator and the stainless steel rotor. Water is fed into the PSS Shaft Seal for cooling/lubricating the seal faces on high-speed vessels. The stationary carbon stator is attached to the nitrile bellow, which is attached to the stern tube (shaft log). Rotor  The rotor is made 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 for maximum holding power. The stainless steel rotor further polishes the carbon stator during the initial hours of operations. Carbon Stator The high-density, resin-impregnated carbon stator is manufactured from an advanced composite that is first mixed and 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 of time, unlike a lip seal or a plastic face seal. In addition, the high density of the carbon greatly increases longevity and wear resistance. As a result, several commercial vessels have recorded over 40,000 engine hours (over 4 1/2 years of continuous operation) on the same original components. Bellows The bellows on the Type A seal are molded out of a Nitrile compound. Nitrile is known for its good resistance to petroleum products. In addition, it provides the best combination of durability, strength, and elasticity necessary for this application. Hose Barb For high-speed vessels (12+ knots), a positive water supply is required to be plumbed to the PSS Shaft Seal for lubricating and cooling the seal faces. Please review the PSS Shaft Seal Installation Instructions for more information on pickup points for water supply. In most cases, a slow-speed boat (less than 12 knots) that does not have a bearing on the shaft log does not require positive water feed and can simply 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. This will ensure the vent hose is never below the water line, even with significant healing. PSS Shaft Seal Installation Instructions have more details on venting the seal. Specifications: Temperature Limits: 5°F to 225°F (-15°C to 107°C) Pressure Limits: 15 PSI (1 BAR) Shaft RPM Limits: 10,000 RPM Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance) 316SS / Nitronic 50: Faced to 9-12 Ra Bellows Material: Molded Nitrile - PVC Shaft Diameter: 45mm Stern Tube Diameter (inch): 3-1/4" to 3-3/8" Approximate Length: 9.2175 in. Approximate Compression: 1 in.  Rotor Diameter: 3.75 in.  Stern Cuff Length: 2 in.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 2" SHAFT 3 1/4" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 1/2" SHAFT 3 1/4" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 3/4" SHAFT 3 1/4" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal 1-1/2" Shaft 3-1/4" Tube Shaft Diameter: 1-1/2" Stern Tube Diameter (D): 3-1/4" to 3-3/8" Total Length (A): 9.175" Total Length (compressed) (Compressed A): 8.175" Rotor Diameter (B): 3.75" Carbon Cuff Diameter (C): 3.25" Stern Cuff Length (E): 2" The PSS Shaft Seal is the number one selling marine mechanical seal worldwide and is installed as standard equipment by many of the worlds most reputable boat builders / yards. The PSS Shaft Seal is also recognized as the premiere retrofit (aftermarket) seal on the world market. Certified by Bureau Veritas, ABS & Rina: Boat builders / yards recognize the advantages and value of installing the PSS as it eliminates the maintenance, constant adjustment & cost associated with traditional packing type glands. Aside from these benefits, the PSS Shaft Seal helps to eliminate water in the bilge (100% water tight) & wear to the propeller shaft. The PSS Shaft Seal can be easily retrofitted and is available for shafts ranging from 3/4" (20mm) to 6" (150mm). The PSS Shaft Seal is a mechanical face seal that 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 vessels stern tube with hose clamps and the carbon flange is attached to the front side of the bellows with hose clamps. The stainless steel rotor is fit on the shaft in front of the carbon flange. The stainless steel rotor is used to compress the bellows before the collar is secured to the shaft with set-screws. This compression (pre-load) maintains contact between the faces and allows the PSS to compensate for the thrust from the propeller. The carbon flange is bored larger than the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration problems. The stainless steel collar is sealed to the shaft by two o-rings that are recessed into the bore of the collar. These o-rings rotate with the shaft and stainless steel rotor and do not experience wear during operation. **As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. PYI suggests as preventative maintenance that the PSS bellow be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced." Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1" SHAFT 2" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1" SHAFT 1 1/2" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1" SHAFT 2 1/4" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 1/8" SHAFT 1 1/2" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 1/4" SHAFT 2" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 1/2" SHAFT 2 1/2" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 1/4" SHAFT 2 1/4" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 1/4"" SHAFT 2 1/2" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

PSS Shaft Seal Maintenance & Parts Replacement Kit FOR 1 1/2" SHAFT 2 1/4" TUBE As with any rubber hose below waterline, the PSS bellows must be inspected on a regular basis for any sign of wear, aging or chemical deterioration. The PSS bellow should be replaced in six year intervals. During bellows replacement it is recommended the o-rings & set screws in the stainless steel rotor also be replaced. Bellows may need to be more frequently inspected in an environment where non-sealed batteries emit sulfuric acid. Sulfuric acid vapor will accelerate rubber deterioration, as will an ozonater. The Maintenance Kit includes the items you need to properly maintain your PSS Shaft Seal. Included in the kit is one (1) PSS bellow, two (2) O-rings, five (5) set screws, four (4) new hose clamps and an allen key.

3" Shaft - 5-1/2" Stern Tube The PSS Shaft Seal is the #1 selling marine mechanical seal worldwide and is installed as standard equipment by many of the worlds most reputable boat builders and boat yards. The PSS Shaft Seal is also recognized as the premiere retrofit (aftermarket) seal on the world market. Boat builders and boat yards recognize the advantages and value of installing the PSS as it eliminates the maintenance, constant adjustment & cost associated with traditional packing type glands. Aside from these benefits, the PSS Shaft Seal helps to eliminate water in the bilge (100% water tight) & wear to the propeller shaft.  How Does it Work? 1. Two nitrile o-rings seal the stainless steel rotor to the shaft and will not experience wear. 2. A primary set screw and a backup set screw (2 sets) are used to secure the stainless steel rotor to the shaft. 3. A seal is created between the two flat surfaces of the carbon stator and the stainless steel rotor. 4. Water is fed into the PSS Shaft Seal for cooling/lubricating the seal faces on high speed vessels. 5. The stationary carbon stator is attached to the nitrile bellow, which is attached to the stern tube (shaft log). Rotor The PSS stainless steel rotor is slid down the shaft and is secured to the shaft with set screws at 90° for maximum holding power. Precision tolerances are maintained by computer controlled lathes. The faces have a number 9 micro finish and are perpendicular to the bore to prevent run-out as the collar rotates. The carbon graphite stator will polish the face of the rotor during the first few minutes of operation. The stainless steel rotor should not need to be replaced under normal operating conditions. The stainless steel rotor used on the PSS Type A Shaft Seal is made from 316L stainless steel.  Carbon Stator The high density, resin impregnated carbon/graphite stator is a composite that is first mixed, molded and then formed under pressure. The blanks are then baked, machined and lapped. The face of our carbon is finished to a flatness of 4 helium light bands (measured .000044" of variation over entire lapped surface). The grade of carbon used in the PSS has an operating temperature over 500° Fahrenheit (+260° Celsius), and cannot melt if the seal runs dry, unlike a rubber lip seal or plastic face seal. The high density of the carbon greatly increases the 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. The carbon should not need to be replaced under normal operating conditions.  Bellow The PSS Type A Shaft Seal bellow is made from rubber (Nitrile), and has a temperature rating of -25°F to +225°F (-31°C to +107°C). Nitrile is known for its resistance to weathering. Nitrile rubber is exceptionally resistant to oils and non-polar solvents. It also offers good gas impermeability, abrasion resistance, and better thermal stability than most general purpose elastomers.  Hose Barb For high speed vessels it is required that a positive water supply be plumbed to the PSS Shaft Seal for the purpose of lubricating and cooling the seal faces. There are many sources of water supply, review the PSS Shaft Seal Installation Instructions for more information and note all plumbing must follow the standards and practices of proper boat plumbing. In most cases a slow speed boat that does not have a bearing the shaft log does not require positive water feed and can simply be "vented". Ideally the vent line will be run at least 2-3 feet above the water line and is close to the center line as possible to ensure the vent hose is never below the water line, even if the boat heels. Review the PSS Shaft Seal Installation Instructions for more details on venting the seal.