Cobalt Digital Inc 190, Manual, Page: 41 / 64

P
ROPELLERS
P
ROPELLERS
- G
ENERAL
Nothing is more important to the proper performance of your boat than the
condition of the propeller(s). Even minor damage (often invisible to the naked eye)
can adversely affect the boat’s performance. Common symptoms of damage to
propellers are a sudden drop in RPM, vibration or sudden loss of speed.
A propeller is measured by two dimensions: 1) the diameter; and, 2) the pitch. The
diameter is determined by measuring the distance from the center of the propeller to
the tip of one blade and multiplying that figure by two. Pitch is expressed in the
number of inches a prop will advance in a solid medium in one revolution.
Operational characteristics of your boat, including its speed, may change due to
several factors: atmospheric conditions; additions of extra equipment and
accessories or passengers; marine growth on the bottom; and, engine condition.
Other factors include damage to the prop(s), tides, water temperature and direction
of wind. Some of these factors are directly correctable by repair or maintenance.
Others are beyond human control.
INCORRECT PROPELLER APPLICATION CAN CAUSE ADVERSE
HANDLING CHARACTERISTICS. DO NOT CHANGE TYPE OR SIZE OF
PROPELLER WITHOUT CONSULTING YOUR COBALT DEALER!
S
TAINLESS
S
TEEL
Some Cobalts are standard equipped with stainless propellers. In this instance, do
not substitute aluminum propellers. Adverse handling and top speed characteristics
may be experienced.
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