Up for sale is a genuine, factory-original Michigan Wheel Aqualube marine water-lubricated sleeve bearing, precision engineered to deliver world-class propulsion shaft alignment and protection. Known throughout the industry as the "Dare" model size, this heavy-duty cutless bearing features a superior marine-grade centrifugally cast bronze outer shell. It is internally bonded with a specially compounded, oil-resistant, and chemical-resistant nitrile rubber lining using advanced factory vulcanization techniques. Purpose-built for commercial vessels, yachts, and high-performance inboards, this bearing uses integrated longitudinal water flutes to establish a consistent hydrodynamic wedge film. This advanced fluid layer absorbs impact shock, isolates powertrain noise, flushes destructive grit out of the system, and protects your expensive propeller shaft from severe abrasion.

Key Features

Centrifugally Cast Bronze Shell: Machined using superior, high-grade marine bronze to provide maximum resistance against galvanic corrosion and harsh saltwater environments.
Advanced Hydrodynamic Fluting: Features continuous interior longitudinal grooves that trap incoming water flow to form a frictionless fluid layer, even at low operating speeds.
High-Abrasion Rubber Compound: Formulated with a tough, 70±3 Shore hardness nitrile rubber core engineered to let sand pass directly into flushing channels rather than embedding in the walls.
Elite Shell Bond Integrity: Proprietary manufacturing bonds the inner rubber lining to the bronze shell with a tensile strength that meets or exceeds the structural limit of the rubber itself.
100% Quality Inspected: Every single piece undergoes rigorous dimensional tolerance testing at the factory to guarantee direct mechanical compatibility and drop-in fitment.

Technical Specifications

Brand: Michigan Wheel Marine
Product Line: Aqualube Bearings
Part Number / SKU: 930002
Model Designator: "Dare"
Shell Material: High-Grade Marine Bronze / Brass
Liner Material: Specially Compounded Nitrile Rubber
Shaft Inner Diameter (I.D.): 3.000 Inches (3")
Outer Diameter (O.D.): 4.000 Inches (4")
Product Length: 12.000 Inches (12")
Wall Thickness Spec: 1/8 Inch
Operating Temperature Range: Extreme -13°F to 185°F (-25°C to 85°C) limits
Normal Safe Working Load: 36 PSI capacity
Operating Speed Range: Compatible with shaft line speeds from 100 to 6,900 feet per minute

Installation & Wear Warning Notes

Forced Water Applications: While bearings fully submerged inside propeller struts or underwater pumps naturally receive adequate fluid supply, if you are installing this unit inside a tight stern tube or a marginal-flow forward shaft log location, a dedicated, forced water-injection feed line must be piped into the housing to ensure constant lubrication.
Routine Maintenance Check: Even when running in pristine, sand-free deep waters, all elastomeric cutless bearings will experience natural structural wear over extended operating windows.

It is highly recommended to manually measure shaft clearance tolerances every single time the vessel is hauled out for winterization, dry dock storage, or routine hull maintenance.
Please carefully verify your exact propeller shaft diameter, strut barrel internal dimension, and overall length requirements prior to placing your order. Feel free to send a message if you have any questions!