How to Cure Boat Porpoising

Anyone who has ever hung over the side or bow -- the front -- of a boat that's moving through the ocean has watched porpoises jumping and leaping in the boat's wake. This is fine for a marine mammal, but when your boat jumps and leaps like a porpoise, that's an undesirable condition. You can prevent porpoising, if your boat is equipped with trim tabs, by adjusting those tabs to change the way your boat's hull interacts with the water.

Instructions

    • 1

      Launch your boat. Move the boat clear of the boat ramp at slow speed.

    • 2

      Press the bottom of both trim-tab rocker switches, usually found either on the dash or near the throttle control. The bow -- the front -- of the boat will appear to nosedive somewhat.

    • 3

      Push the throttle forward, increasing the boat's speed, until the boat begins to porpoise. Press the top half of both trim-tab rocker switches to raise the trim tabs, until the boat stops porpoising.

    • 4

      Increase the boat's speed. If the boat begins to porpoise again, press the top half of the trim-tab rocker switches to raise the trim tabs farther. Continue to raise the trim tabs until the boat stops porpoising.

    • 5

      Repeat, until the boat is at full speed and no longer porpoising.