Connecting SeaStar Hydraulic Steering Lines

Don't make the one fundamental mistake many people fall prey to when installing the hydraulic lines for a SeaStar front-mounted cylinder steering system. 

Front Mounted Cylinder Models

It's way too easy to forget that the hydraulic lines for front-mounted cylinders that run from the helm to the steering cylinder MUST BE SWITCHED ACROSS from port to starboard and vice-versa.

Seastar hydraulic steering system

Crossing a pipe from one side of a system to the other is the total opposite of what we might think is correct, which is why a lot of boat owners follow their instincts and connect the starboard side of the helm pump to the starboard side of the cylinder, and the port side to the port side. The SeaStar front mounted steering cylinder is essentially a solid rod that is secured to the transom, surrounded by a moveable sleeve (the cylinder itself) that is attached to the tiller of the outboard motor.

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SeaStar Hydraulic Steering: How It Works

The inside of the cylinder is divided into two separate chambers, or reservoirs, at either end. When hydraulic fluid is pushed into one of the reservoirs, it forces the reservoir to expand in order to accommodate the extra hydraulic fluid. 

hydraulic steering outboard

This need for expansion forces the cylinder's body to slide along the central shaft toward the side into which the additional hydraulic fluid is being introduced. Because the cylinder is attached to the front of the outboard, it pulls the outboard in the same direction, while the outboard's rear end pivots in the opposite direction. 

steering a boat

If the port side hydraulic line from the helm were to be connected to the port side of the cylinder, when the helm was turned to port, the hydraulic fluid would push into the port side of the cylinder, making the cylinder and the front of the outboard angle to port, while pivoting the rear of the outboard and the prop to starboard. This results in the boat turning to starboard, hence the need to switch across the port and starboard hydraulic lines between the helm pump and the steering cylinder.

SeaStar hydraulic steering system's helm has the hydraulic connectors clearly marked "P" and "S", and the hydraulic pipes have color coordinated end caps: red for port and green for starboard. However, the cylinder end connectors aren't marked, so it's up to you to remember to switch the port line over to the starboard side and vice-versa when installing a front mounted SeaStar hydraulic steering cylinder.



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