Trim tab not working

bayson

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My '05 Gulfstream has one trim tab not working. I can hear the pump but not moving. Could it be low fluid, bad pump? Where is the pump located. I hear it by the helm.

Just added Seastar power steering. This is fantastic.
 

DennisG01

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Could be low on fluid - sounds like you've located it, so go ahead and check the level.

Check electrical connections - especially red and green (port/stbd). Reverse the hydraulic lines at the pump - that will tell you if the issue is at the hydraulic cylinder or at the pump.
 
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seasick

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If one tab works but the other doesn't AND you hear the pump running when you try to operate the non working tab, it is less likely that fluid is low. It is still possible but I would suspect a stuck check valve.
Try to move the tab by hand without applying power. You shouldn't be able to move it and if it does, it is needing bleeding.
Listen to the sound of the pump tp try and tell if it seems to be running freely or sounding like it is facing resistance. It is also possible that your tab is frozen in place or your actuator is frozen. If so, you should hear the pump working harder on the bad side.

What did you add Seastar fluid to? Trim tabs maybe.. oy.
 
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DennisG01

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I was wondering about that comment about the Seastar, too. At first I thought he added power steering fluid to the trim tabs, as well... but then I figured it was just a completely separate and unrelated comment... just to confuse us!

FYI, you CAN push a tab DOWN manually by hand, even in a fully functioning system. That is normal to be able to do that.
 
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bayson

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Sorry, I do wander off course.

I just had the Seastar system added last week. Might have something to do with the problem? I'll do a little more checking before calling the mechanic.
 

DennisG01

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I just had the Seastar system added last week. Might have something to do with the problem? I'll do a little more checking before calling the mechanic.
No, that shouldn't have anything to do with it.

Got any leaks on the inside or outside of the transom?
 

glacierbaze

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Go to post #3 for Tabman's troubleshooting guide. Tom was irreplacable.
On my Seafarer, the HPU is under the starboard vee berth.

 

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switch the 2 lines at the pump should tell you if it’s the pump
 

seasick

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As Dennis said, that shouldn't matter as long as when you press the switch to move the tab that is not working, you are certain you hear the pump running,
 
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seasalt

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I had the same problem with my Bennett tabs. The first time it happened, I replaced the whole hydraulic unit at the suggestion of my mechanic ( who I no longer use!) . The tabs worked for a hour or so then same thing happened.The tab would stay stuck down unless I bled the pressure off from the hydraulic unit. It drove me nuts and I went long time with no tabs. It turned out the problem was one little wire shorting at the helm switch ( barely noticeable) and it was causing the port solenoid, in my case, to burn out. I replaced the solenoid and with the short on the switch fixed, everything is happy again. I think that when someone was messing with wires at my helm, the switch connection was not put back properly. I have a basic euro switch but the positive and negative screws are quite close together on the back of the switch. I hope this might help.
 
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bayson

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Waiting for the mechanic, hopefully this week. I'll let everyone know what I find. Thank you'll.
 

bayson

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Actually I was there with the mechanic and after discussion I decided I prefer the electric for many reasons to me.
 

DennisG01

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That's fine, it's your boat and you can certainly do what you want, but...
How did you verify the actuators where bad and it wasn't just an o-ring? BOTH actuators are bad?

However, generally speaking, hydraulics are longer lasting than electrics with most hyd setups easily lasting 30 years without any attention. 'Course, it would be easier/less expensive to repair what's there or replace like with like - but again, it's your boat so... dealer's choice.
 

blindmullet

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Bad actuators. Replacing with electric trim tabs.
That's very odd for both of them to be bad. I do like the Bennett company and their support but nothing wrong with Lenco's or a conversion kit. On a trailered boat I think you're fine with electric. They are so much more responsive.
 

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Assuming your old tabs are Bennett, they have been making the electric Bolt tab system for a number of years now. Pretty sure you can buy their electric actuators, and use your existing tabs, if you want to save some money.