SeaStar HA5430H Hydraulic Steering Fluid 946 ml

Purpose-Formulated for Marine Hydraulic Steering

SeaStar HA5430H Hydraulic Steering Fluid is engineered specifically for the demands of marine hydraulic steering systems. Unlike generic hydraulic fluids or automotive power steering fluids, this product is blended to meet the unique requirements of SeaStar, BayStar, and Hynautic helms and cylinders. Using the correct fluid is critical to maintaining smooth, responsive steering and protecting the internal seals and components of your system from premature wear.

Advanced Fluid Formulation

The HA5430H fluid incorporates a carefully balanced combination of performance additives designed to keep your steering system operating at its best:

• Viscosity stabilizers maintain consistent fluid performance across a wide range of operating temperatures
• Anti-wear ingredients reduce friction and extend the service life of internal components
• Defoaming agents prevent air entrainment that can cause spongy or erratic steering response
• Corrosion inhibitors protect metal surfaces from moisture-related degradation

Compatibility and Application

This fluid is designed for use in SeaStar, BayStar, and Hynautic hydraulic steering systems. It is suitable for initial fills, top-ups, and complete fluid changes. When servicing your steering system, always refer to your helm and cylinder manufacturer's instructions for the correct fill procedure and fluid capacity. Slight variations in fluid colour from bottle to bottle are normal and will not affect system performance.

Why Regular Fluid Maintenance Matters

Hydraulic steering fluid degrades over time due to heat cycling, moisture ingress, and mechanical shear. In the Canadian marine environment—where boats may sit idle through long winters and then operate in demanding conditions during the boating season—regular fluid inspection and replacement is particularly important. Old or contaminated fluid can lead to sluggish steering response, increased helm effort, seal deterioration, and ultimately costly repairs. Checking your fluid level and condition at the start of each season is a straightforward way to protect your investment.

Specifications

• Volume: 946 ml
• MFG Part Number: HA5430H
• Appearance: Transparent, yellow tinted fluid
• Odour: Mild petroleum odour
• Specific Gravity: 0.844
• Kinematic Viscosity: 14.1–15.1 mm²/s at 40°C
• Flash Point: 164°C / 327°F (Cleveland open cup)
• Chemical Family: Petroleum hydrocarbon mixture
• Transport Classification: Not regulated (DOT)
• NFPA Flammability Rating: 1
• NFPA Health Rating: 0
• Maximum Handling Temperature: 70°C (158°F)

Key Features 

• Formulated specifically for SeaStar, BayStar, and Hynautic systems — ensures compatibility with OEM seals and components
• Viscosity stabilizers — maintains consistent steering feel across seasonal temperature swings
• Anti-wear additives — reduces internal component friction and extends steering system service life
• Defoaming agents — prevents spongy helm response caused by air entrainment
• Corrosion inhibitors — protects internal metal surfaces from moisture-related degradation
• Transparent fluid with mild odour — easy to inspect for contamination during routine checks
• High flash point — safe for use in engine compartment environments
• Not classified as dangerous goods for transport — straightforward to ship and store