Trim tab deflection

[dar636]

Hello all,

Were hauled out and found that the trim tabs on our 76 YF are only traveling approx 3" down. The pump is full and runs normally when hitting the helm switches.

Does anyone know what the full deflection down measurement is supposed to be and what would cause them to not travel fully? Is there a limit switch adjustment? Is this as far as they should travel?

 

[racclarkson@gmail.com]

Actually sounds right. They’re not true trim tabs but more leveling tabs.

 

[SKYCHENEY]

Sounds right to me as well. They put stops in the cylinders depending on the application.

 

[jrbrein]

When I first got my boat, I thought the tabs motion was somewhat limited.

I disconnected the actuators then removed both tabs and removed multiple layers of marine growth and bottom paint from the articulating joint and significantly improved the range of motion of the tabs. Then I reconnected the actuators.

All better...

Jon

 

[oscarvan]

When I first got my boat, I thought the tabs motion was somewhat limited.

I disconnected the actuators then removed both tabs and removed multiple layers of marine growth and bottom paint from the articulating joint and significantly improved the range of motion of the tabs. Then I reconnected the actuators.

All better...

Jon

So how many inches of travel on the trailing edge of the foil would you say you have now?

 

[jrbrein]

So how many inches of travel on the trailing edge of the foil would you say you have now?

About 3 - 4", maybe a bit more. I also keep them retracted when not in use to keep the actuator arms from fouling.

Jon

 

[Avenger]

That's interesting. My Boat Levelers manual says to keep them extended when not in use. My guess would be to prevent fouling of the cylinder bore that might cut the seals on the pistons, or pack up material that would limit travel.

 

[86Hat41]

That travel is about right. Actually it might only be 2 1/2". Bennett makes an actuator that goes in additional 1 in. Also they sell "drop fins" that work excellent. I have both. I actually now have too much tab. But that is a good thing when full of fuel and water. Very, very sensitive adjustments and it's like relearning your boat all over again, but worth it.

 

[dar636]

Thanks everyone, FYI Sam's agrees - short travel, not really trim tabs but leveling tabs. I was never able to find technical data to back up the info but moving on.... She's back in the water good to go.

 

[jrbrein]

That's interesting. My Boat Levelers manual says to keep them extended when not in use. My guess would be to prevent fouling of the cylinder bore that might cut the seals on the pistons, or pack up material that would limit travel.

That is interesting...not what I would have thought but thank you for that. I will need to download the manual since I never got one with the boat.

I have a diver on my boat monthly and will have to make sure those pistons are kept clean.


Jon