For high speed vessels (12+ knots), a positive water supply is required to be plumbed to the PSS Shaft Seal for the purpose of 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 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 will be as close to the center line as possible. This will ensure the vent hose is never below the water line, even with significant heeling. PSS Shaft Seal Installation Instructions has more more details on venting the seal.
The PSS Bellows offer the best combination of durability, strength & elasticity, and in addition to carrying standard sizing, can be engineered in a number of configurations to meet various application requirements. The most common configuration is composed of two ends (connectors) and a convolution region where the ends provide the assembly interface and the convolution (bellows) region provides for the design application travel / required flexibility.
The silicone bellow material meets and exceeds the properties listed in SAE J20 Class A and provides superior low and high temperature resistance. The Fluorosilicone Cover creates an oil and fuel resistant barrier protecting the exterior surface from the possibility of damage from splash or spill.
The bellow is reinforced with multiple plies of aramid fabric.