About Steering

Steering systems come in a variety of versions to fit most boating requirements. Established systems include mechanical, hydraulic, and power steering; a newer steering system is electrical, or “steer-by-wire.” With all four systems, a steering wheel attached to the system will activate the direction the boat moves in.


Mechanical steering uses a cable that connects the helm and steering wheel to the engine. As you move the steering wheel, the cable moves the engine and boat in the direction you turn the wheel. Rack and rotary mechanical systems are both available with a “no-torque” option, which provides a locking system that does not allow the wheel to spin if you remove your hands.


Hydraulic steering is a system typically seen in boats with larger engines. It uses a series of valves and hydraulic fluid to move the boat in the desired direction. Hoses connect the helm (steering wheel) and the steering cylinder on the engine. When the steering wheel is turned, the fluid is pushed through the cylinder, causing the bracket to move the engine. In turn, the fluid returns to the reservoir under the steering wheel and helm, allowing the system to maintain pressure.

Different sizes and styles of hydraulic systems are available, including solid one-position mounts and tilt mounts as options. Helms can vary based on the hydraulic valve system inside, which controls the amount of effort required to steer the boat. Also available are systems sized to engine horsepower and boat applications. Systems typically are categorized in groups: 150 hp and below, 150 hp to 300 hp for typical boats, and a high-performance category for boats capable of exceeding 60 mph. Various systems also allow multiple engine installations.

Power Steering

Power Steering on outboards is relatively new to the marine market. Engines like Mercury’s Verado use power steering and operate much like an automotive system. The system is pressurized and a pump keeps the fluid moving in the system. “Finger-tip steering” describes the feel that you experience when driving a boat using power steering. The system itself is similar to hydraulic steering, in that it has a helm and cylinder with hoses, but power steering has an additional pump or motor.

Sterndrive engines can also use power steering. Today, most sterndrives use a mechanical helm with a cable that activates a hydraulic valve connected to a pump on the engine. This is the most common power steering system today. Mercury recently introduced power steering for high-torque applications using the power steering-style helm. This is a complete system that connects hoses from front to back, giving the driver the same power steering performance experienced with the outboard power steering system.


This is a relatively new feature that was launched with our Axius and Zeus systems, which use a joystick to control twin engines. Steer-by-wire eliminates the need to have hydraulic hoses that run from the steering wheel back to the engine steering system. Rather, is is a SmartCraft (digital) system that allows steering wheel position to be relayed to the engines via wires.

Big Tiller

These new tiller handles can be used on most Mercury outboard engines and are sold as a kit. There are different versions, designed for particular engine families: 40-60 HP FourStroke; 75-115 HP FourStroke and OptiMax; and even a power steering Big Tiller for the most demanding requirements (150 hp and up).