SeaStar HC6345-3 Outboard PRO Front Mount Hydraulic Boat Cylinder

SeaStar HC6345-3 Outboard PRO Front Mount Hydraulic Boat Cylinder 

The Dometic SeaStar HC63453 is a high-performance, front-mount (pivoting) hydraulic steering cylinder purpose-built for high-speed outboard applications. Engineered to meet the demands of today’s heavier, higher-horsepower engines, the PRO cylinder features a rugged marine-grade body, a new 8-hole end-gland sealing system, and positionable stainless-steel ORB (-5) hose fittings for superior sealing and easier installation.

With enhanced durability, cleaner hose routing, and full compatibility with SeaStar PRO helm pumps and PRO Kevlar hoses as well as standard SeaStar helms within spec-the HC6345-3 is ideal for bass boats, performance center consoles, and other high-speed rigs that demand precise, responsive steering under real-world conditions.

Key Features & Benefits

• High-Performance PRO Cylinder - tuned for high-speed bass/sport boats with ultra-low friction and minimal free play
• 1500-PSI System Compatibility - intended for use with SeaStar PRO helms & hoses
• Full Engine Tilt Compatibility - maintains smooth, precise steering through the full tilt range
• Robust, Corrosion-Resistant Design - marine-grade body, stainless shaft, and hardware built for harsh saltwater use
• Upgraded 8-Hole End-Gland Sealing System - proprietary seal package for long life and easier service
• Positionable Stainless -5 ORB Fittings - modern ORB ports (replaces legacy 1/4" NPT) for cleaner, leak-free hose routing
• Smooth, Responsive Steering Feel - optimized with SeaStar PRO helms; compatible with standard SeaStar helms within application limits
• Variable Lock-to-Lock Turns - steering feel/ratio sets with helm displacement selection
• Warranty: 2-Year Limited
• Made in Canada!

Will This Cylinder Work on My Boat?

Technical Specifications

• Direct Replacement for the HC6345 (earlier PRO generation; “-3” adds -5 ORB ports and internal upgrades)
• Mount Style: Front Mount, Pivoting (balanced PRO cylinder)
• System Compatibility: SeaStar PRO 1500-PSI systems
• Shaft Diameter: 0.75" (19 mm)
• Stroke Length: 8.00" (203 mm)
• Cylinder Bore: 1.375" (~35 mm)
• Displacement (Fluid Volume): 8.34 cu in (136.6 cc)
• Ports / Fittings: Positionable stainless -5 ORB hose fittings
• Overall Dimensions (approx.): Width 21-3/4" (552 mm), Depth 4-7/8" (124 mm), Height 2-5/8" (67 mm)
• Weight (approx.): ~9.5 lb
• Included in the Box: Complete PRO cylinder with positionable -5 ORB fittings, HA5438 Filler Kit & Instruction Manual

Kits That Include the HC6345-3

Spare Parts for the HC6345-3

Related Parts

Downloads & Resources

Other SeaStar Parts

Questions?

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• Formerly Teleflex, SeaStar is now Dometic Marine
• Seatech Marine Products, Inc. is an authorized dealer, and service center for Dometic Marine
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