Trim Tabs Won't Stay Down

[Agoose]

I have a 1986 Century Meridian, 28 feet long with Bennett Trim Tabs. The original problem was that starboard side trim tab would not go down. The fluid level was low so I added fluid at the dock and worked both tabs up and down. Went out three days later and the tabs worked fine for a couple of times but then they started coming up on their own. Tied up to a mooring and they still wouldn't work. Got on top of them and was able to bounce them up and down using my bodyweight. The pump sounds like its working and you see the fluid level change when you hit the switches but they won't move. Any ideas?

 

[Bob_VT]

Re: Trim Tabs Won't Stay Down

Where is the fluid leaking? Probably time to either replace of rebuild the cylinders (if possible). SOund like the seals are near gone and fluid is bypassing them.

 

[Tabman]

Re: Trim Tabs Won't Stay Down

agoose,

If the system is loosing fluid and the Tabs are retracting on their own then, as Bob points out, replacing the O-rings in the actuators (rams) will likely solve the problem. It is easy to do and we can send the parts at no charge.

If the Tabs are retracting but the system is not loosing fluid then the valve seats in the pump may be damaged or fouled. Those to can easily be changed and I can send you those at no charge as well.

If you send your name and address to me at Tmcgow@bennetttrimtabs.com I would be delighted to send you the parts and instructions in the mail.

 

[Agoose]

Re: Trim Tabs Won't Stay Down

Someone mentioned that maybe I had air in the system and I had to bleed it.
Someone else mentioned that I had to exercise the tabs more after adding fluid and they would self bleed. Are any of these scenarios likely?

 

[rndn]

Re: Trim Tabs Won't Stay Down

Sounds like you have something leaking. The o-rings mentioned above are a likely culprit.

 

[dingbat]

Re: Trim Tabs Won't Stay Down

Someone mentioned that maybe I had air in the system and I had to bleed it.
Someone else mentioned that I had to exercise the tabs more after adding fluid and they would self bleed. Are any of these scenarios likely?

The tabs are self bleeding. Run to the full up and full down positions and few time and that should do it.

With that said, even with air in the system I don?t see how they would deflect more than an inch or so. Follow Tabsmans suggestions and you can?t go wrong.