Bennet trim tab ?

[skillz48047]

I have a 1987 sea ray 390 EC
It has the standard black double rocker switch to control the tabs, along with the bennet auto tab controller (i will attach pics of both)
My question is im in the process of remodeling the dashboard/helm area and i want to replace the trim tab double rocker switch with a newer light up version that shows the tab positions
Question is can that style of a controller be retrofit to work with my system?

 

[Carpediem44DB]

Ive been meaning to ask the same question, I assumed that the system would need to be changed with some sort of position sensor on the tabs or in the actuators. I'd love to know where my tabs are. I had positon indicating switch panel on my Rinker 350 and loved it. I think the tabs even stowed up when the engines shut down.
Edit: I just looked into it and there are sensors to add to the tabs so it is something i will look into the next time I have the boat pulled, in about 3 years if all goes as planned
Carpe Diem

 

[Henry Boyd]

I have a 1987 sea ray 390 EC
It has the standard black double rocker switch to control the tabs, along with the bennet auto tab controller (i will attach pics of both)
My question is im in the process of remodeling the dashboard/helm area and i want to replace the trim tab double rocker switch with a newer light up version that shows the tab positions
Question is can that style of a controller be retrofit to work with my system?

There are a couple things to consider that are usually combined. The first is tab indicators; lights that show the position of the tabs and that’s all they do. These basically have sensors in the tab piston and are wired to a box that controls the light display on the dash.

The other item is auto trim control. Auto trim involves the same sensors and control box as the indicators, but adds another box that measures the inertial orientation of the boat, and measures that change in boat attitude (trim). This additional box provides a memory space for the set attitude position, and auto control for the tabs.

The operation is pretty simple. On flat water you manually set the optimimum trim attitude for the boat and then memorize that position in the system. When you engage the system it will move the tabs until the memorized attitude is achieved. And as water conditions change, the system will continue to adjust the system. I’ve found though that manually getting the boat in the ballpark first before setting creates the smoothest ride.

As a DIY I think it makes sense to install a combined auto trim and indicators, rather than just the indicators. The work will be the same and the benefits greater.

 

[atrick]

I got the automatic system with indicators and I would think trying to retro fit a existing system would cost more than buying a new unit and installing. I got the system on the 21' boat that we use for skiing/tubing and the auto system is great as people are moving around in boat and it keeps it level which helps the skier and the indicaters are great when you come off plane to pick up a fallen skier/tuber and can't remember what position you had tabs in.

 

[Henry Boyd]

I got the automatic system with indicators and I would think trying to retro fit a existing system would cost more than buying a new unit and installing. I got the system on the 21' boat that we use for skiing/tubing and the auto system is great as people are moving around in boat and it keeps it level which helps the skier and the indicaters are great when you come off plane to pick up a fallen skier/tuber and can't remember what position you had tabs in.

If you mean the piston sensors, wiring and control boxes, all that stuff comes out anyways and is replaced with the auto/indicator stuff. No need to replace the pistons or tabs. The sensor piston top just replaces the existing one. You do need the boat out of the water because you have to id/measure the existing piston travel to order the right size sensor.

 

[Skybolt]

The auto trim is ~$450 and the piston sensors are just the piston tops with rods, two different length's ~$60. The original pistons are still used and the tops are unscrewed and the new ones installed with the correct rod. There are only two length's, standard and short. In most case's it s easier to buy new pistons and just swap them out when out of water.

That system works pretty well. There is also another option, they also sell NMEA 2000 sensors ~$120 which are the same type of sensor as the indicator ones except N2K, Garmin also sells an analog to N2K sender to convert the fore mentioned indicator sensors to N2K. The N2K is displayed on most MFD's as a pop-up window that displays a bar graph. Both N2K and led indicator are separate from the Auto Trim unit as @Henry Boyd mentioned.

I went with the N2K and the auto retract setup and put the trim switches in the dash switch panel, carling switches.