Specifications

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Engine & Steering Controls
Points to consider when selecting a mechanical steering system
Plan the most direct cable route. Keep the number of
bends to a minimum and do not bend the cable less than
the minium specified bend radius. The trim settings of
outboards and sterndrives can markedly affect steering
loads and boat maneuverability. The motor trim tab
should be set in accordance with the motor manufacturer's
recommendations. The boat should also be tested for ease
of steering through the full range of motor trim angles
since varying trim angles can change steering loads on
any given system.
The mounting position of the outboard also affects the
steering and boat handling characteristics. Mounting
specifications established by the boat builder and engine
manufacturer should be adhered to strictly.
The proper steering system is a critical factor in achieving good boat handling
performance and safe operation. The combination of engine horsepower,
propeller torque, hull design and boat speed exerts varying loads on steering
systems. Because the resulting steering forces vary considerably from boat
to boat and motor to motor, extreme care must be taken to ensure the steering
system you select matches the application.
The following guidelines have been developed to assist you in making a
steering system selection, and in particular alert you to potential problem
areas.
•Steering forces increase considerably when the speed and horsepower of
the boat increases. High performance boats often leave and re-enter the
water momentarily, creating High shock loads on the steering system. In
addition, certain hull designs may have a tendency to lose stability at high
speeds, a condition commonly called "chine walk."
•The speed at which instability begins to occur varies significantly among
different type boats. A Morse twin cable or hydraulic steering system is
generally recommended for boats moving at higher speeds.
•Corrosion of steering cables can lead to stiff operation and complete
seizure. The steering cable should be regularly inspected for cracks or cuts.
If found, the cable should be replaced. If there are no signs of cracking, the
cable output end and the engine tilt tube should be cleaned thoroughly,
coated with a quality marine lubricant, then properly reassembled and
maintained according to the engine manufacturer's specifications. Corro-
sive buildup can be minimized through this simple routine maintenance.
Whenever possible, the boat builder and dealer should select Morse cables
which all have Stainless Steel output ends to reduce corrosion, especially
on boats used in salt water. Even then, if a boat is not going to be used for
extended periods of time, it is recommended to completely remove the
cable output end from the thru tube and properly prepare for storage.
•The routing of steering cables is also an important consideration. Multiple
bends in the cable and small bend radii will contribute to cable backlash
and steering inefficiency. Cables should be routed with as few bends as
possible and with the optimum radii achievable.
•Excessive cable length results in excess bend radius, contributing to
excess backlash and cable inefficiency. If an installation requires a 16 ft.
cable, a 16 ft. cable should be used. Do not add unnecessary length.
•Larger boats with displacement hulls and inboard rudders can create
steering loads that exceed the capacity of the mechanical steering systems
commonly used on runabouts. Hydraulic steering systems are better suited
to function under high steering loads.
•Although Morse Controls designs and manufactures steering systems to
meet existing industry standards, the boat builder and dealer are ultimately
responsible for determining the particular steering system best suited for
the intended application. For further technical assistance in specifying
steering systems contact Morse Controls.