SeaStar 1.7 Sport Tilt Hydraulic Steering Kit HK6400TS-4 for Outboard Engines up to 350 HP

The SeaStar HK6400TS-4 is a complete 1.7 Sport Tilt hydraulic steering kit built for outboard-powered boats, giving single or dual non-power-assisted outboard engines smooth, precise steering feel. The kit centers on a 1.7 cubic inch displacement helm that delivers 5 turns lock-to-lock for confident, responsive control at the wheel, paired with a pivot mount outboard steering cylinder (HC5345-3/58-3) finished in black. The cylinder features positionable stainless steel O-ring (ORB) fittings that simplify hydraulic hose routing and provide a sealing system designed to resist saltwater intrusion and compression set over time. Tilt articulation reaches 48 degrees across 5 positive lock positions, with factory-installed lubrication for consistent operation. Two quarts of SeaStar HA5430 hydraulic steering fluid are included to fill the system; hydraulic hoses are sold separately (SeaStar HO51xx hose kit, ordered by length) so the run can be sized to the boat. Construction uses stainless steel and rubber components, including a soft rubber boot at the cylinder. The system is built and certified to American Boat & Yacht Council (ABYC) and International Standards Organization (ISO) requirements and is suitable for cruisers, runabouts, center console boats, and offshore fishing boats. It supports single and dual outboard installations up to 350 HP (700 combined HP for counter-rotating dual engines) with boats capable of speeds up to 60 MPH, on engines equipped with an ABYC Standard Engine Tilt Tube.

Specifications

• Brand: SeaStar
• Manufacturer Part Number: HK6400TS-4
• Product Line: SeaStar 1.7 Tilt Steering Kit (Sport)
• Kit Type: Hydraulic Outboard Steering Kit
• Helm Displacement: 1.7 cubic inches
• Steering Turns Lock-to-Lock: 5 turns
• Helm Grip Size: 7-8 inches
• Cylinder Mount Type: Pivot mount
• Cylinder Color: Black
• Cylinder Part Number: HC5345-3/58-3
• Tilt Articulation: 48 degrees
• Tilt Lock Positions: 5 positive lock positions
• Maximum Engine Horsepower: 350 HP single or dual engine; 700 HP combined for counter-rotating dual engines
• Maximum Boat Speed: 60 MPH
• Hydraulic Fluid Included: 2 quarts SeaStar HA5430 hydraulic steering fluid
• Hydraulic Hoses: Sold separately (SeaStar HO51xx hose kit)
• Material: Stainless steel, rubber
• Certification: ABYC and ISO certified
• Weight: 29 pounds
• UPC: 808282390419

Fitment

• Single or dual non-power-assisted outboard engines up to 350 HP (700 combined HP for counter-rotating dual engines)
• Requires an ABYC Standard Engine Tilt Tube
• Suitable for boats with speeds up to 60 MPH
• Supports dual station use with purchase of an additional helm, hose, and fittings (sold separately)

Frequently Asked Questions

What does the SeaStar HK6400TS-4 Sport Tilt Steering Kit include? The HK6400TS-4 kit includes a 1.7 cubic inch displacement front mount helm, a pivot mount outboard steering cylinder (HC5345-3/58-3) in black, and 2 quarts of SeaStar HA5430 hydraulic steering fluid. Hydraulic hoses are sold separately as a SeaStar HO51xx hose kit sized to the installation.

How many turns lock-to-lock does this steering kit have? The helm in the HK6400TS-4 kit provides 5 turns lock-to-lock, which is a standard feel for recreational outboard steering.

What is the maximum horsepower this steering kit can handle? This kit is rated for single or dual non-power-assisted outboard engines up to 350 HP, or up to 700 combined HP when used on counter-rotating dual engine setups.

Does the HK6400TS-4 come with hydraulic hoses? No, hydraulic hoses are not included with the HK6400TS-4. They are ordered separately as a SeaStar HO51xx hose kit, chosen by the length needed for the boat.

How much does the HK6400TS-4 steering kit weigh? The complete SeaStar HK6400TS-4 Sport Tilt Steering Kit weighs 29 pounds.

What materials is this steering kit made from? The HK6400TS-4 uses stainless steel and rubber construction, including stainless steel O-ring (ORB) fittings on the cylinder and a soft rubber boot.

How much tilt articulation does the steering cylinder allow? The pivot mount cylinder included with the HK6400TS-4 allows 48 degrees of tilt articulation with 5 positive lock positions for the outboard engine.

Is this steering kit certified for marine use? Yes, the HK6400TS-4 is built and certified to meet American Boat & Yacht Council (ABYC) and International Standards Organization (ISO) requirements.

What is the difference between the Sport and Classic versions of this steering kit? The Sport version (HK6400TS-4) and the Classic version (HK6400TC-3) share the same outboard steering cylinder, hose kit, and hydraulic fluid, but use different helm styles suited to different helm aesthetics.

Can this kit be used for a dual-engine or dual-station setup? The HK6400TS-4 supports dual, non-power-assisted outboard engines up to 700 combined HP for counter-rotating setups, and can be configured for dual station steering with an additional helm, hose, and fittings purchased separately.

What size grip does the helm on this kit have? The helm included in the HK6400TS-4 Sport Tilt Steering Kit has a grip size of 7-8 inches.

What type of hydraulic fluid should be used with the HK6400TS-4? The HK6400TS-4 is filled with SeaStar HA5430 hydraulic steering fluid, with 2 quarts included in the kit; using non-SeaStar hydraulic fluid or hoses may affect performance and warranty coverage.