Whether they’re hydraulic or electric, trim tabs are among the more useful accessories you can have on a boat. They help get the boat on plane, allow it to stay on plane at lower speeds, let you “balance” the craft by adjusting for weight shifts and improve a boat’s riding qualities in various sea conditions. And, when used in conjunction with trim, the proper use of tabs can enhance top speed in a high-performance hull.
Depending on your experience, you may find it easy to get a feel for trim tab position when the boat is moving. Other operators are never really sure. But once the boat is at rest, it is hard to know what position they are in. Everyone who has tabs on his boat has taken off with them in the wrong position at least once – and probably many times.
CUT SOME SLACK
Trim tab manufacturers such as Bennett and others offer electronic tab-position indicators. These designs typically use a series of light-emitting diodes (LEDs) to display each tab’s position; the more lights that are lit, the lower the tabs are. Generally, these require an electronic sensing device, and the tabs have to move a set distance before the next light either goes on or off.
Stainless Marine, a high-performance accessories manufacturer based in Opa Locka, Florida, offers a simpler and more accurate mechanical system. The company’s No-Slack Indicators are cable-actuated, and the markers on the dash gauge are spring-loaded. This takes the slop out of the cable, regardless of the direction of movement, allowing the indicators to precisely follow the movement of the tabs.
Stainless Marine’s kit consists of: the mounting hardware for the tab; through-transom fittings; two push-pull cables; the sliding indicator at the dash; and two 9006 led bulb that moves with the indicator to show each tab’s position. Kits are also available for most sterndrives, late-model V-6 outboards and jack plates. The tools required to complete the installation are a drill, saber saw, screwdriver and an assortment of wrenches.
There are three important points to consider when planning this installation. First, the hardware that anchors the cable end to the tabs can be mounted on either side of the trim tab cylinder. Check the inside of the transom to see where the cable will come through, as you don’t want to drill into or pass through a wiring harness, fuel line or another component.
Second, when deciding where to install the indicator gauge, make sure there is adequate clearance behind the helm panel for the cable to be attached without forcing an excessively sharp bend. (Bear in mind that the cables attach at the top of the indicator.)
Finally, be sure to measure the cable lengths carefully to keep the cable run as bend-free as possible. Spring tension returns the marker/LED assembly when the tabs are in the up position, and if cable friction exceeds the spring tension, the system won’t work.
The No-Slack Indicators operate smoothly and provide an accurate picture of where the tabs are positioned. When you find the sweet spot between power trim and proper tab positioning, the gauge makes it easy to return to it time and again. There is no longer any excuse for taking off with the tabs in the wrong position.
Although we found the kit’s directions a bit sparse, the system is easy to figure out and the installation is straightforward.
Here’s how our job went:
STEP 1: After checking inside the transom to see where the cable would come through and making sure there were no obstacles, we attached the cable-end mounting point to the trim tab plate.
STEP 2: The cable end disassembles to permit the angled through-hull fitting, rubber seal and sealing nut to be slid onto the cable. This is followed by the mounting bracket and rubber boot.
STEP 3: Here, we’re installing the clamp that holds the outer cable sheath. It is used to adjust the tension of the inner core cable. For a clean look, we installed the through-transom fitting adjacent to the trim tab pass-through.
STEP 4: In our case, the trim indicator cable came through between the trim tab hydraulic lines and our Yamaha sterndrive’s power trim pump.
STEP 5: Use the supplied template when cutting the opening for the faceplate indicator at the helm. Before drilling or cutting, tape the fiberglass to prevent chipping. Because the cables enter from the top of the spring plate, be sure there’s enough room under the helm and that the cables are long enough to make a gradual bend.
STEP 6: Once installed, the indicator gauge sits flush against the instrument panel. Long mounting bolts accommodate panels of every thickness.
STEP 7: Attach the cables to the spring-loaded base plate. Two screws on the base plate can now be adjusted to put a slight bit of tension on the cables. This removes any slop in the system and ensures that each indicator marker/LED will accurately follow the action of the tabs.
STEP 8: The base plate with cables attached can now be secured to the top faceplate. Spacers are provided to ensure a proper fit. The cable attachment point has provisions for inserting the LED marker bulbs, which are then adjusted to just clear the top faceplate indicator. The positive and negative leads of the LEDs should now be wired. Route the negative side to a good ground and the positive wire to the switched side of the ignition. Good job. Now go get yourself a cold drink.