SeaStar HC4645-3 BayStar Outboard Hydraulic Steering Cylinder, Up to 150HP

The SeaStar HC4645-3 BayStar Outboard Cylinder is a compact hydraulic steering cylinder built to upgrade an outboard steering system from mechanical to hydraulic control. Its compact form is designed for smaller outboards up to 150HP and is sized to fit most splashwells, making it a straightforward upgrade path for boats currently running mechanical steering. The cylinder features a precision-manufactured, balanced design and is built under rigid ISO quality control standards for consistent performance. Installation is designed to be easy, letting owners move to hydraulic steering without extensive modification to the transom or splashwell area. With an 8 inch actuation stroke length, a maximum pressure rating of 1000 psi, and a fluid displacement of 7.25 cubic inches, the HC4645-3 is engineered to deliver smooth, controlled steering response at the helm. The cylinder uses a 0.63 inch shaft diameter and is rated for use with SeaStar Steering Fluid. Overall dimensions are 4.60 inches in height, 5.19 inches in depth, and 21 inches in width, with a total weight of 7.06 pounds. This cylinder is intended for outboard applications rated up to 150HP where a compact, splashwell-mounted hydraulic cylinder is required.

Specifications

• Brand: SeaStar
• Manufacturer Part Number: HC4645-3
• Horsepower Rating: 150 HP
• Actuation Stroke Length: 8 inches
• Maximum Pressure Rating: 1000 psi
• Fluid Displacement: 7.25 cubic inches
• Shaft Diameter: 0.63 inches
• Allowable Fluid Type: SeaStar Steering Fluid
• Height: 4.60 inches
• Depth: 5.19 inches
• Width: 21 inches
• Weight: 7.06 pounds
• UPC: 731957932013

Fitment

• Outboards up to 150 HP
• Fits most splashwells

Frequently Asked Questions

What does the SeaStar HC4645-3 do? The SeaStar HC4645-3 BayStar Outboard Cylinder is a hydraulic steering cylinder that lets you upgrade an outboard steering system from mechanical to hydraulic control.

Will the HC4645-3 fit my outboard? This cylinder has a compact design made for smaller outboards up to 150HP and is sized to fit most splashwells.

What is the maximum pressure rating of this cylinder? The HC4645-3 BayStar Outboard Cylinder has a maximum pressure rating of 1000 psi.

How long is the actuation stroke? The HC4645-3 has an actuation stroke length of 8 inches.

What hydraulic fluid should be used with this cylinder? The SeaStar HC4645-3 is rated for use with SeaStar Steering Fluid.

What are the dimensions of the HC4645-3 cylinder? The HC4645-3 measures 4.60 inches in height, 5.19 inches in depth, and 21 inches in width.

How much does the HC4645-3 weigh? The SeaStar HC4645-3 BayStar Outboard Cylinder weighs 7.06 pounds.

What is the shaft diameter on this cylinder? The HC4645-3 has a shaft diameter of 0.63 inches.

Is the SeaStar HC4645-3 easy to install? Yes, the HC4645-3 BayStar Outboard Cylinder is designed to be easy to install.

What is the fluid displacement of the HC4645-3? The HC4645-3 has a fluid displacement of 7.25 cubic inches.

Is the HC4645-3 quality controlled? The HC4645-3 is built under rigid ISO quality control with precision manufacturing for a balanced cylinder.