by Conrad & Judy Kreuter
Dear Boat Talk: My boat always seems to ride with the bow up in the air at cruising speed. Would trim tabs be useful in correcting this condition? Are they easy to install? HR, San Remo, NY
Dear HR: Regardless of whether you have inboard or outboard power, trim tabs add a tremendous benefit to efficiency, safety, and performance. They solve a multitude of problems including list or lean to either port or starboard, bows that ride too high, sterns that plow too low, boats difficult to plane, or boats that ride wet and rough. It’s guaranteed they will get you up on plane faster by providing more lift in the transom like the flaps on an airplane wing. A well balanced powerboat gets on plane faster, handles better, and runs with less fuel eating drag which is important when fuel is approaching $2.00 or more a gallon.
With average mechanical skills, you should be able to install a trim tab system yourself. A project of this type will take about 4-5 hours.
There are several suppliers of trim tab systems. They all produce a complete line of trim tab systems and controls to fit any size boat. In the world of trim tabs, size does matter. Stop by your local marine supply store and ask for assistance to determine the correct size trim tab for your application.
All of the trim tab manufacturers offer a complete installation kit. Packaged within the kit you will find a complete set of components to install the system. Included in the kit is a pair of stainless steel trim tabs with actuators, waterproof rocker switch, either a hydraulic power unit, or electrically operated actuator assembly, all hydraulic lines and fittings and an installation video. Each manufacturer also makes a number of accessories, such as an indicator to determine the position of the tabs, and an automatic tab retractor that resets the tabs to neutral each time the ignition is turned on.
With basic hand tools and with the help of a complete set of instructions packed with each kit, you should be able to successfully install the system. Begin by locating the trim tabs on the transom of the boat. Make sure they are as close to the port and starboard chine as possible, never closer than eight inches from the centerline of the drive or outboard.
For those of you with a hydraulic trim tab system, install the hydraulic pump unit at the transom of the boat. Two hydraulic lines will run from the pump unit, one to each port and starboard trim tab actuator. Connect the main power leads from the pump unit to the main battery and run the control cable to the dashboard. Locate the control switch where it will be accessible easily while underway. Mount the switch and connect the control wires. Fill the hydraulic pump unit with the automatic transmission fluid. Once filled, cycle the port and starboard trim tabs up and down and top off the hydraulic pump unit.
If you selected an electric trim tab system, there will be no hydraulic pump unit and hydraulic lines to install. Instead connect the control wires coming from the actuators directly to the control switch at the dash. Installation is the same as described above.