Trimming a Boat

July 23, 2018
Trimming a Boat
What actually is Trim on a Boat?

If you ask a bunch of boaters the question what is trimming a boat, you be amazed at how many answers you get.  Likewise you’ll get a variety on answers.  Furthermore, you get a several statement answer.   I find this somewhat entertaining but in the same vein, I too had difficulty putting my finger on the definition.  It’s actually pretty simple, are you sitting down?  When you trim a boat you are adjusting the draft.  That’s it.  Draft is from the deepest part of our boat to the waters surface.  In other words the part of our boat that is in the water.  You should know what the draft is on your boat.

Why even use the Trim on a Boat?

Trimming a boat not only affects the boats speed and fuel consumption but also the steering ability.  If the boat is out of balance due to passengers and or cargo, we may find ourselves going off course.  We can trim out a bit of listing or rolling.  To clarify, always make sure you are doing your best to load gear, cargo, and passengers as evenly as possible. The most common uses for trim are as follows.  First is for activity.  Second is for comfort.  Third is for speed and fuel economy.

Activities that require a slow speed my require trimming the boat in or down.  As a result we have nice stable, steady vessel.  We may trim a boat out or up through choppy waters.  So this provides more comfort for passengers.  We may also trim the boat up or out for speed and fuel economy.  Lets say we set the throttle arm at halfway.  This results in a speed of say 15 knots.  By utilizing trim we may get another 5-7 knots using the same throttle setting.  Therefore improving both speed and fuel economy.

What Effect does Trim have on my boat?

A boat with too much bow down or bow up can lose speed and be less responsive to steering. Too much “out” or “up” trimming of the motor can bring the propeller too close to the water surface.  Consequently this will result in sucking air into the blades causing the loss of thrust. You’ll hear sudden increases in the motors RPM’s and feel the boat slowing down. Too much “in” or “down” drives the bow down into the water resulting in the laboring of the motor and its components.  Find the “sweet spot” for whatever activity you are engaging in, conditions, and or speed you want to travel. Regardless of activity the boat should glide smoothly through the weater.


Above all, be smart, be safe, and remember there are no egos when passengers’ lives are in your hands.

Please visit our Public Course Schedule to view all of the classes we have available for you.  Zoom classes are now available.  There has never been an easier way to get your Boating Certificate

Here is a great video from the United States Coast Guard regarding Boating safety:  Boating Safety with the U.S. Coast Guard – Bing video