The trim tab on an outboard motor is located above the prop, on the bottom of the cavitation plate. When not set properly, it causes the boat to push or pull to one side. This is especially noticeable when operating tiller motors, often resulting in arm fatigue from fighting the motor’s tendency to pull to the right or push to the left. On console boats, it seems easier to steer either left or right when the trim tab isn’t set properly.
A water test is the only way to identify which way the boat wants to go. With an evenly distributed load, bring the boat on plane and trim up to the desired trim level for your boat to level out and run smoothly. If the boat steers equally to the left and right, or the tiller arm doesn’t push or pull to one side, the trim tab is set properly. However, if the boat wants to move to the left or right, the trim tab needs adjusting.
Adjusting the trim tab is easy. Out of the water and from behind the motor, loosen the trim tab’s retaining bolt. If the boat wants to go to the right, move the trim tab to the right. If the boat wants to go to the left, move the trim tab to the left.
Make small adjustments and water test until the boat tracks straight.
Originally published in the June 2020 issue of Ontario OUT of DOORS.