Key West Boats 1720CC, Manual

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• Once on plane, the engine should be trimmed out a little to avoid a bow
down condition called “plowing.” Plowing can cause “bow-steering” or
“oversteering” and inefficiently consume horsepower. In this condition,
if attempting a turn or encountering a diagonal moderate wake, a more
abrupt turn than intended may result.
☐ WARNING ☐
To avoid possible serious injury or death, adjust the
engine to an intermediate position as soon as the boat
is on plane to avoid possible ejection due to boat spin-
out Do not attempt to turn the boat when the engine is
trimmed extremely under or in.
High speed operation in rough water requires quick reactions and
adjustments to maintain control. Know your limits and stay within them.
Always keep one hand on the steering wheel and the other on the throttle;
constant adjustments are necessary for rapidly changing conditions. Small
inputs of throttle and steering are exaggerated at high speed.
Watch the tachometer to keep the engine within the full throttle operating
range. See the engine Operator’s manual for the proper tachometer
reading at full throttle.
Propellers
The propeller converts the engine’s power into the thrust needed to propel
the boat. Care and selection of your propeller is very important. Check the
engine operator’s manual for the horsepower rating and operating range
of the engine to determine the proper propeller for desired performance.
Propellers are identified by two numbers such as 14 x 21, and a material
identification, such as aluminum or stainless steel. In the number sequence
the first number is the diameter of the propeller and the second is the pitch.
Pitch is the angle of the blades expressed in the theoretical distance a
propeller travels in each revolution. In the above example, the pitch is 21,
or each revolution pushes the
propeller 21” through the water.
A 21” propeller is considered
“higher’’ pitched and a 15”
propeller is considered “lower’’
pitched.
Keep these guidelines in mind
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