trim tab trouble...

[AFD]

So i thought i had a trim tab issue because it seemed while cruising at any speed that the tabs did nothing. I'll get a picture from side tomorrow to show the down angle but the port tab doesn't extend as low as the starboard piston. they both retract to the same angle but the port one doesn't go down very far. also it seems that the tabs don't go down very far at all. they retract to above the hull plane and that seems wrong to me, i feel that they should only go in line with the hull or just slightly beyond flush but they retract quite a bit. I don't see any other holes to imply that they have been replaced but it just seems that for a 10,000 + lb boat that the tabs would be able to give it some push. the size doesn't seem overly small but it is the angle that is throwing me off. I had smaller boats so this is my first boat with tabs but family has had much larger boats and i have been fairly competent with them.

If i unbolt the starboard tab from the piston it hangs at exactly the same angle as if the tab was forcing it. seems like it is designed to stop there and the piston does as well.

the port one when i unbolt it from the piston hangs at the same angle as the starboard one but the piston will not push it to that point.
you tell me what you think. The tab is unbolted from the piston and the tab is hanging at the lowest it will go because of the hinge design, the small black plastic mounting point is usually all the way against the tab but there is almost an of space that the starboard one does push that this one doesn't. I measured the piston length extended as well and the port one is 15/16 shorter than the starboard one.






how would i extend the piston further like the other one to make the tabs extend equal amounts?

should i reposition the mounting holes on the tabs and adjust the hinge mechanism to make sure they will angle further or is this a normal amount of angle for fully down?

Thanks everyone
Anthony


also, looking at the bottom in the pictures. this is after power washing. what kind of paint would you put on it? what kind of surface prep does the bottom need before i apply paint? i want to get some of this done before the winter and I am super busy with the baby on the way. thanks again

 

[hottoddie]

Looking at your pictures I can tell that the bottom brackets are on the wrong side of the trim tabs plate. They belong on the inside and this would completely change the geometry and how far they extend.

 

[Havana Shamrock]

Here you can see the proper mounting position hottoddie is correct , I'm assuming they where removed at one point and installed improperly

 

[electricaldoctor]

Should the angled down fin be pointed down or does that even matter?

 

[duckmnn]

As said before the rams go on other side if fin

 

[Ten Years Gone]

Yep...these guys are correct. But if you need more help, my advice would be to call the manufacturer. I had the pleasure of speaking with one of the tech's at Bennett about a month ago looking to put larger planes on mine. The people at Bennett are very helpful, and love to discuss their product. Give them a call and you will learn more about trim tab systems than you ever thought possible.

 

[AFD]

thanks everyone.
the tabs cannot go on the other side of that bracket without removing the hinged plastic mounting tab as the pistons do not rotate and if i were to rotate just the mounting point it would locate the holes on the bottom and not the back. unless the mounting points were removed seperately from the piston and reinstalled incorrectly. moving them to the inside of that stainless tab would also bind the top of the piston where it mounts to the transom. as it sits in the pictures the piston is at rest so i believe the ones on my boat were installed this way correctly.

yup, just checked an old email with a picture sent by another member with the same boat and his are mounted the same as mine in my photo.

electricaldoctor, I'm not sure what you're asking.

 

[AFD]

BTW, those pictures are with the screws out and the tab is just hanging at it's full "droop"

 

[electricaldoctor]

The ends are bent up. most trim tabs that I have seen have the ends bent down. Does that really make a difference or not??

 

[hottoddie]

thanks everyone.
the tabs cannot go on the other side of that bracket without removing the hinged plastic mounting tab as the pistons do not rotate and if i were to rotate just the mounting point it would locate the holes on the bottom and not the back. unless the mounting points were removed seperately from the piston and reinstalled incorrectly. moving them to the inside of that stainless tab would also bind the top of the piston where it mounts to the transom. as it sits in the pictures the piston is at rest so i believe the ones on my boat were installed this way correctly.

yup, just checked an old email with a picture sent by another member with the same boat and his are mounted the same as mine in my photo.

electricaldoctor, I'm not sure what you're asking.

AFD you are incorrect re: the pistons rotating. They will rotate but you may need them to be "midstroke" as they will be harder to rotate when at full extension or retraction. Take my word as I have this more than once before.

 

[Tabman]

Hello,

We make many different custom Trim Planes and Actuators (pistons) for SeaRay. Can you tell me the total stroke for each actuator?

Also the dimensions of the Trim Planes as well as how far above the plane of the hull the trailing edge is when the Tab is fully retracted? Place a 3-4 foot straightedge under the hull to measure this.

Tom McGow
Bennett Marine

 

[SloBurn]

I would just rotate the black mounting plates 180 degrees if possible, without rotating the pistons. They are meant to swivel for proper operation, and need to go inside of trim tab, not outer side.

 

[AFD]

Hello,

We make many different custom Trim Planes and Actuators (pistons) for SeaRay. Can you tell me the total stroke for each actuator?

Also the dimensions of the Trim Planes as well as how far above the plane of the hull the trailing edge is when the Tab is fully retracted? Place a 3-4 foot straightedge under the hull to measure this.

Tom McGow
Bennett Marine

Tabman

I'll have dimensions for you tomorrow. thank you. I will also have better pictures showing the trailing edge at fully retracted and fully extended. can you verify for me if the tabs must go in front vertical plate or is it just the most common installation method? I have seen pictures of 2 other 290's with the same orientation as mine so i assume at this point that mine are in the correct orientation for my application.

thanks
Anthony

 

[Tabman]

Anthony,

It sounds like the actuators are in the proper position, can you get me a wide shot photo of the Tabs and Actuators showing the tops of the actuators? If the Actuators are not binding or striking that mounting plate they are in the correct position.


Tom
Bennett Marine

 

[AFD]

the actuators are not binding or striking the tab in any way. i feel like they are just not very effective if at all and the port on is deffinately not extending as far as the starboard one, my boat has a starboard list as the water and holding tanks are on the starboard side and my fat pooper is always there too, even if just at the dock. water tank is always full 28 gallons and the holding tank never had more than a few gallons in it but the head is also on that side. when cruising the starboard side is also where most people are sitting as there is only a port lounger where my wife always sits or lays so i always tried to tab down the starboard tab as mush as possible to counter some of that but never got any reaction from the bow that it was doing anything.

I will try to get pictures of everything including the 4' level showing the hull line with the tab fully down and up tomorrow but i have just been crazy busy getting things ready for the offspring. thanks for your help. also i saw photos of another 290 same year and their tabs were the same positioning as mine.

thanks again tabman

 

[Tabman]

OK, sounds good! While you are taking pictures, see if you can get a "whole" transom shot so I may see the position of the Tabs.

Thanks,
Tom
Bennett Marine

 

[AFD]

i am at a work computer so i cannot upload pictures until after work hours...Dept rules, no laptops until after business hours. I can tell you what i have for measurements and upload photos after 6pm.

starboard piston 4" extended
port piston is 3-5/8" fully extended.

up they are 1-1/2" retracted

with a 4' level on the hull extended beyond the tab at the rear of the tab i have
starboard side 2" below the hull
Pot side 1-1/2" below hull

I unfortunately cannot give you a full transom shot because i had the boat placed very close to my fence. i will upload the pics i have of the tabs and measurements tonight but the transom shot i cannot get.

as i look down the hull, you would think that 2" of depression at the tab would be significant enough to pick up that side of the stern but while traveling i felt NO effect at slow cruising speeds and honestly can't remember much if any effect while on plane. The boat had a constant starboard list. I'm not worried about her behavior at the slip or at anchor but while moving it is a noticeable lean. i'm curious if the tab is not very well sized for the weight and size of the boat. boat has twin 5.0's and usually full water tank, empty or damn near empty holding tank and does not have a gen. the boat performs well but always seems to turn to the starboard without the wheel moving. i have one standard ad one counter rotation prop so the drives aren't causing any walking.

 

[Tabman]

The standard stroke for an actuator is 2-1/2", so it appears that the port actuator is not a standard actuator. Replacing the actuator with a standard one would give you more stroke. You would only have to replace the bottom portion of the actuator, leaving the upper hinge attached to the transom.
I would kike to know the measurements of the Trim Tabs. Undersized Trim Tabs are common when they are installed at the factory. If the Trim Tabs are square to the transom, then adding 3" dropfins to capture water pressure that normally escapes out the sides and channel it aft for increased lift is an option.





Tom
Bennett Marine

 

[AFD]

The standard stroke for an actuator is 2-1/2", so it appears that the port actuator is not a standard actuator. Replacing the actuator with a standard one would give you more stroke. You would only have to replace the bottom portion of the actuator, leaving the upper hinge attached to the transom.
I would kike to know the measurements of the Trim Tabs. Undersized Trim Tabs are common when they are installed at the factory. If the Trim Tabs are square to the transom, then adding 3" dropfins to capture water pressure that normally escapes out the sides and channel it aft for increased lift is an option.





Tom
Bennett Marine

looking at the diameter of the actuator and the size of the the tab you posted, i am willing to bet mine are the same size and my boat is 10' wide and weighs around 10,000 according to sea ray. i'm leaning towards undersized. also, the top of mine are't exactly "hinged" they have a wide flexible point that is very rigid one side to side but does allow some movement front to back for normal range of motion. i'm going to grab my laptop now and see if it shows in the pictures i took. how hard is it to change the bottom portion of the actuator?


starboard side



port side



I don't know what happened to the pictures of the measurements for the actuators but with the numbers you were able to tell there is a problem.

also you can see that the side tabs are strangely set up with a vertical closer to the center line of the boat and a dropped fin side on the outer edge of the tabs. they are also quite small for the size of the boat judging from the pictures you posted of a boat noticeable smaller with relatively the same size tabs and actuators.

how is a lower portion of an actuator removed/replaced?

thanks for your help tabman...

 

[Tabman]

It's not hard at all, I can walk you through it, it's about a 15 minute job.

Tom
Bennett Marine