Steering System - Boston Whaler 21 Justice Series Operation & Maintenance Manual

Section 4

Steering System

The steering system installed in your boat is a Teleflex
Sea Star II hydraulic system. This is a manually oper-
ated, closed-loop hydraulic system requiring no pumps
or electric motors. The system consists of the follow-
ing components:
• Steering wheel
• Sea Star II helm pump
• Teleflex hydraulic hoses
• Front-mount steering cylinder
• Sea Star HA-5430 fluid
The Sea Star II helm pump is an axial piston pump
specifically designed for manual steering. It has a
built-in lock valve to prevent the steering load of the
engine from feeding back to the boat operator. The
lock valve will not allow the outboard engine to move
unless the steering wheel is turned. The lock valve
also contains a pressure relief valve which provides
over-pressure protection for the mechanical compo-
nents, the hydraulic hoses, and the fittings.
When the steering wheel is turned clockwise, hydrau-
lic fluid is pumped out of the helm unit, into the star-
board hose and then into the steering cylinder. As the
fluid is pumped into one side of the steering cylinder,
an equal volume of fluid is displaced from the opposite
side. The steering cylinder body moves to port. The
cylinder body is connected directly to the engine steer-
ing arm. The engine steering arm also moves to port
and puts the boat into a starboard turn. The fluid dis-
placed from the steering cylinder returns to the helm
pump reservoir through the port hose.
Turning the steering wheel counter-clockwise results
in a similar response, but in the opposite direction.
When no course correction is required, the lock valve
holds the outboard engine in place.
Return the steering wheel to the CENTERED position
when you turn the outboard engine OFF.
4-4
Boat Systems