bill91817

Hi all hoping anyone can help
tabman? ! :-)
I have a new to me boat and the trim tabs are jammed down about 1.5 inches - I have removed the pump (stuffed) and the lines from the tabs are unblocked- Have taped them into empty bottles and a bit of fluid came out- i have tried (in the water) to push the tabs up and they won’t budget - I have put a lot of force behind giving them a push and they won’t budge! I know they should close up further as they are set in a recessed space in the hull - the boat is punching down a bit and I really want them up - can’t lift the boat for 2 months due and it’s summer here (Australia!) and I want to use the boat!
any help would be greatly appreciated
cheers
bill

captbone

Disconnected like that the actuators should return up. I think you need new actuators. Look at a diagram and you can see how they a held in place at the tab end with a pin. If the top of the actuator is above the water, you can replace them in the water.

Tabman sadly passes away and is missed. RIP.

bill91817

Thanks for the reply - so sorry to hear about tabman - he helped me out from afar a few years back - RIP
my actuators are below waterline - no doubt they need replacing but was hoping to get them up prior - assume they have water In them and are seized?

captbone

I would removed the pin from the bottom of the actuator or unbolt them from the tab and tie them up until you can haul it at a later date.

jhackl

Unbolt them from the tab end and tie them up.

RCL

You can buy individual pieces for the actuators. I had a shaft fail ( p o used the tab as a step to get in and out of the boat and broke it and bent the tab itself) and bought a new one for like 10 bucks. You just need to know what's wrong.

Do the tabs go down by any chance? And is it both? It sounds like since the boats in the water that the hinges on the tabs may be blocked ornother may be growth on the shaft preventing them from coming up

OceanCityHank

did you bleed the hydraulic lines in case of existence of excessive air? did you top off hydraulic fluid?

Rolandt03

his tabs are stuck in the down position, he has disconnected the lines and has the lines secured into empty bottles incase fluid comes out. he is tryin get them up but will not go up even if he manually pushes upward on them!

Dacman

Is there growth on the ram rods at the bottom of actuators ? As stated they should want to return to up position with the lines disconnected by spring pressure.
Maybe the lines are kinked? Do you have access to the fittings behind transom on the actuator mounts?
Have you checked the tab pockets in hull to see that there’s not a croc wedged in there?

bill91817

Hi - I can move them down about half an inch - but that’s it- no growth on shaft and nothing blocking them between hull and trim plate - I think I will need to unbolt them and wire them up ! Cheers

RCL

This is for both correct? If so it's really odd that both are acting the same way and stuck in the same position. Did they ever work before? Inside the actuators if i recall correctly is a spring that sits between the bottom of the actuator and the top of the piston itself. When fluid is pumped in, the piston is forced down lowering the tab and compresses the spring. When fluid comes out, the spring forces the tab back up. It almost sounds like you may have contaminated fluid that built up crud around the top of piston which is not allowing the piston to move freely. With the hoses off the tabs, w hat you can do is take the pin or unbolt the bottom of the actuator from the tab itself. Rotate the shaft left and right and see if it breaks it free. Just becarefull there is a lot of force being applied by the spring. If you take the pin out put a bolt and nut in it so it doesnt shoot all the way up into the actuator.

RCL

11/2 inch usually isn't a full throw for most tabs. He never said full extension.

SeaPro48

1.5 inches is not much. Can you borrow a Go Pro and snap a few pics? Can you get the boat out of the water with them down (eventually) without hurting them or the boat? I would let it eat until it is out of the water.
Spring tension should have raised them when the lines were disconnected. There is nothing blocking the cylinder (like mentioned, a ring of growth around the piston preventing retraction). There are no gators (or crocs?) getting wedged preventing them from retracting. That would leave some type of internal corrosion or blockage. If that's the case, a new system is in order. Since the tabs are mounted and all holes are drilled, it shouldnt be too bad when the time comes. The little check valve balls in the pump are very sensitive to corrosion, so it would be best not to reuse anything if you find a mess inside the cylinders when you finally get them out. Def not an underwater job.
Pics, man, pics.
Good luck! Keep us posted.
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PeteH

I thought they made 2 sizes of actuators.

Is it possible someone replaced the original actuator with the longer model?
There isn't much to the piston assembly, a couple of Orings and a spring in there.

PeteH

Just looked it up, bennett makes 2 sizes of actuator piston
13 3/4" and 11 3/4"

If someone replaced the lower part of the actuator (piston and cylinder) with the longer model you are never getting them to retract fully.

Arsinek

Just had the Bennet to Lenco kit put on my boat. Was not a fan of the Bennets.

Dacman

I think you can count the rings molded on the actuator case to see what models you have and their specs on throws. Extension

Measure the distance from tab mounting point fully retracted to transom mounting plate when you tie them up before getting new ones.