Specifications

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Engine & Steering Controls
Understanding Mechanical Advantage
Understanding Mechanical Advantage
By design, every control has a specific mechanical advantage factor. Simply stated, mechanical advantage means that because you
are using a lever to create motion at the other end of a control system (move the throttle or shift mechanism on the engine itself)
it requires less effort at the control handle than it would if you were pushing directly on the engine's throttle or shift mechanism.
As an example, if an engine required 15 lbs. of force to move its shift lever and you were using a control with a mechanical advantage
of 2.77, you would divide the force by the mechanical advantage to determine how much effort must be exerted at the control lever
handle to create the needed 15 lbs. of force.
Force
----------------------------------- = force required at the control lever
Mechanical Advantage
15 lbs.
------------ = 5.42 pounds of force required at the control lever.
2.77
Understanding a control's mechanical advantage and the amount of force to be overcome at the engine is very important when
specifying the appropriate control.
Single function
control, single en-
gine
Single function control, auxillary engine
Dual function controls, twin engine
Dual function
control, single
engine
Parallel system using transfer units
Single function con-
trols, twin engine
Multiple Station Installations
Dual or multiple station applications almost exclusively use single-function two lever
controls. There are two basic system designs recommended for multiple stations. One is
the parallel system and the other is the series system.
The parallel system consists of cables from each control station running all the way to the
clutch and throttle at the engine. This configuration is utilized when cable runs are
relatively short and direct.
An option for use with parallel dual stations is a transfer unit. A transfer unit permits the
two clutch and/or the two clutch cables from the controls to be connected to a single cable
leading aft to the engine. Transfer units are used where long or difficult cable paths make
parallel installations costly or difficult to operate.
In a series control system, the cables run from controls to the lower station controls, and
then to the engine. This method is generally used for longer, more difficult cable runs.
When to utilize a parallel system or a series system is dictated by the total degrees of bend
in the cables as measured by the sum of the degrees of all bend radii. Thisdirectly affects
the efficiency of cable action. The configuration that gives the control system the fewest
degrees of bend is the one that should be empolyed.
Control Head Mountings
A final choice in engine control styles is the type of mounting.
Morse Controls makes a wide variety of controls so that the boat
owner can tailor the control to the boat's exact needs and their
own preferences.