MerCruiser 3.0 MPI, Owner'S Manual

Page: 34 / 114

Section 2 - Getting to Know Your Power Package
Page 26 90-899883272 MARCH 2008
For best performance trim the sterndrive unit so that the boat bottom is at a 3‑5° angle to
the water.
3 - 5
mc79528
Trimming sterndrive unit up/out can:
• Generally increase top speed
• Increase clearance over submerged objects or a shallow bottom
• Cause boat to accelerate and plane off slower
• In excess, cause boat porpoising (bouncing) or propeller ventilation
• Cause engine overheating if trimmed up/out to a point where any cooling water intake
holes are above the water line
mc78529
Trimming sterndrive unit down/in can:
• Help the boat accelerate and plane off quicker
• Generally improve the ride in choppy water
• In most cases, reduce boat speed
• If in excess, lower the bow of some boats to a point at which they begin to plow with
their bow in the water while on plane. This can result in an unexpected turn in either
direction called bow steering or over steering if any turn is attempted or if a significant
wave is encountered.
mc79530
Single Engine Trim/Trailer
Single engine applications will have a button that can be pressed to trim the sterndrive unit
up or down.
To raise the sterndrive unit for trailering, beaching, launching, low speed (below 1200 rpm),
and shallow water operation push the trim button to raise the sterndrive unit to the full up/
out position.