Trim Tab Adjustment - Mercury 8 Bigfoot 4-Stroke User Manual

FEATURES AND CONTROLS

Trim Tab Adjustment

Propeller steering torque will cause your boat to pull in one direction. This steering torque is a normal thing that
results from your outboard not being trimmed so the propeller shaft is parallel to the water surface. The trim tab
can help compensate for this steering torque in many cases and can be adjusted within limits to reduce any unequal
steering effort.
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NOTE: Trim tab adjustment will have little effect reducing steering torque if the outboard is installed with the
anti‑ventilation plate approximately 50 mm (2 inches) or more above the boat bottom.
Operate your boat at normal cruising speed, trimmed to the desired position. Turn your boat left and right and note
the direction the boat turns more easily.
If adjustment is necessary, loosen trim tab bolt and make small adjustments at a time. If the boat turns more easily
to the left, move the trailing edge of trim tab to the left. If the boat turns more easily to the right move the trailing
edge of trim tab to the right. Retighten bolt and retest.
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