Mavimare GF300HD Outboard Hydraulic Steering System up to 300HP

The Mavimare GF300HD is a reinforced, heavy-duty hydraulic steering system designed for single outboard engines up to 300 HP, or twin outboard setups up to a combined 600 HP when using counter-rotating propellers and a tie bar.

Features

• Balanced cylinder design: Provides smooth, precise, and responsive steering with equal effort and turns in both port and starboard directions.
• Easy installation: Frontal mounting "bullhorn"-style cylinder with high-performance guide; designed for straightforward setup on most outboard engines.
• Universal compatibility: Works with most major outboard brands (e.g., Yamaha, Mercury, Honda, etc.). A specific adapter kit (X.393) is required for certain Suzuki models like 150A/175A/200A.

Specifications

• Steering wheel turns (lock-to-lock / band-to-band): Approximately 5.2 turns
• Pump displacement: 27 cm³ per revolution.
• Cylinder volume: 130 cm³ (balanced chambers).
• Maximum system pressure: 60 bar (relief valve at 70 bar).
• Helm pump weight: ~3.4 kg (approximate for GM2-MRA01).
• Mounting: Frontal mount cylinder; pump supports up to ~20° tilt (bleed horizontally if steeper).

Components

• Helm pump: GM2-MRA01 (7-piston design, flush/semi-flush mount with square bezel kit included; 27 cm³ displacement per turn; max pressure 60 bar / ~870 PSI, with relief valve at 70 bar).
• Steering cylinder: MC300HD (front-mount balanced bullhorn type; bore Ø 34 mm; volume 130 cm³; stroke 200 mm).
• Hoses: 2 × 7.5 m (15 m total) SAE 100 R7 5/16" hydraulic hoses (fittings pressed on one end; can be ordered pre-fitted on both ends for custom lengths).
• Fittings: Chrome-plated brass ORB-style fittings (kits such as GTN7X10916ORB and AC38/T916).
• Hydraulic fluid: 2 liters of Mavimare-approved oil (e.g., H-AP51, equivalent to Shell Tellus T15 or similar ISO 15 viscosity fluid).
• Accessories: Fast-connection filler tube kit (X.372) for easier bleeding/filling.