Conditions Affecting Operation; Weight Distribution (Passengers And Gear) Inside The Boat; Bottom Of Boat; Cavitation - Mercury 496 MAG Bravo Owner's Manual

CA958

Weight Distribution (Passengers And Gear) Inside The Boat

Shifting weight to rear (stern):
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Generally increases speed and engine rpm.
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At extremes, can cause boat to porpoise.
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Causes bow to bounce in choppy water.
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Increases danger of following wave splashing into boat when coming off plane.
Shifting weight to front (bow):
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Improves ease of planing.
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Improves rough water ride.
•
At extremes, can cause boat to veer back and forth (bow steer).
CA959

Bottom Of Boat

To maintain maximum speed, the boat bottom should be:
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Clean, free of barnacles and marine growth.
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Free of distortion; nearly flat where it contacts the water.
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Straight and smooth, fore and aft.
Marine vegetation may accumulate when boat is docked. This growth must be removed before operation; it may
clog water inlets and cause engine to overheat.
CA9

Cavitation

Cavitation occurs when water flow cannot follow the contour of a fast-moving underwater object, such as a gear
housing or propeller. Cavitation permits the propeller to speed up, but the boat speed to reduce. Cavitation can
seriously erode the surface of the gear housing or propeller. Common causes of cavitation are:
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Weeds or other debris snagged on propeller or gear housing.
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Bent propeller blade or damaged gear housing skeg.
•
Raised burrs or sharp edges on propeller or gear housing.
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Conditions Affecting Operation

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