Bennett trim tabs

seasick

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Can you see a leak? Hopefully it is the tab piston and not an oil leak from another source. To be sure, retract the tabs, take a run for a while to 'scrub' off the oil, then and dock. Let sit until the water is calm and see what the slick looks like. Then cycle the tabs down once or twice. If the piston is leaking, it will be obvious by the new oil slick. Note that it could be a bad fitting or hose;If so, you should be able to see/feel oil on the outside of the tab cylinder.
If its the cylinder, replacing is the best approach.
 

Uncle Joe

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I had so many problems with my Bennett hydraulic trim tabs over the years that I replaced them with Lenco electric tabs and never looked back.
 

DennisG01

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Overall, Bennett's are very reliable (that's not to say that Lenco's are bad - they are not). But in terms of 'law of averages'... this comes from dealing with many of these on my own/friend's boats... along with many, many that I see at the shop. Lenco's do have a higher failure rate. For the most part, Bennett's are one of those things that 'just work' and you don't think about them for decades. But certainly, any mechanical item can fail. In addition to what Seasick mentioned, I'd also suggest getting in touch with Bennett once you figure out what's going on. They are extremely helpful.
 

wrxhoon

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I have no doubt that Bennets are very good and long lasting but they are so slow , the electric Lencos i had before were much faster. Bennet provide excellent customer service just like Grady do.
 

DennisG01

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I have no doubt that Bennets are very good and long lasting but they are so slow , the electric Lencos i had before were much faster.
Yes. I'd say easily twice as fast.

It would be a somewhat costly venture to completely convert, though - from a practical standpoint (in my opinion, anyways) it'd be worth simply fixing the Bennett's as it should be relatively inexpensive. Possibly just o-rings.
 
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Uncle Joe

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Yes. I'd say easily twice as fast.

It would be a somewhat costly venture to completely convert, though - from a practical standpoint (in my opinion, anyways) it'd be worth simply fixing the Bennett's as it should be relatively inexpensive. Possibly just o-rings.

I don't mean to bash Bennett.....they have been the standard for a long time...they didn't get that way by putting out an inferior product.....and this problem does sound like a simple O ring.

I just had a lot of trouble with the pump...I had to replace it every 2 or 3 years. I may have been doing something wrong during winterization but it cost me $250+ for the pump each time and it was a pain tearing up the deck and doing the work associated with replacement.

The Lencos were not a big nut as I was able to do the wiring and install them myself. I guess a mechanic would cost a few $$ if you can't do it yourself.
 

DennisG01

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I don't mean to bash Bennett.....they have been the standard for a long time...they didn't get that way by putting out an inferior product.....and this problem does sound like a simple O ring.

I just had a lot of trouble with the pump...I had to replace it every 2 or 3 years. I may have been doing something wrong during winterization but it cost me $250+ for the pump each time and it was a pain tearing up the deck and doing the work associated with replacement.
Oh, no worries. That's really odd that you had to keep replacing the pump - but if I had to keep replacing it, I'm sure I would be looking for alternatives, too.
 
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Ozz043

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Paulfitz, I think you really need to assess out of the water unfortunately. As Dennis has said repairing existing units is definitely the way to go ..... until you physically see the problem there won’t be a remedy available
 

Fishtales

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Strange 3 boats with Bennet tabs and never an issue.
 

seasick

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I don't mean to bash Bennett.....they have been the standard for a long time...they didn't get that way by putting out an inferior product.....and this problem does sound like a simple O ring.

I just had a lot of trouble with the pump...I had to replace it every 2 or 3 years. I may have been doing something wrong during winterization but it cost me $250+ for the pump each time and it was a pain tearing up the deck and doing the work associated with replacement.

The Lencos were not a big nut as I was able to do the wiring and install them myself. I guess a mechanic would cost a few $$ if you can't do it yourself.
I am not aware of any winterization needs for the Bennett system. What exactly have you been doing?
 
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Uncle Joe

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I am not aware of any winterization needs for the Bennett system. What exactly have you been doing?

Actually nothing .....thought maybe I was NOT doing something I should have......it just seemed to me that I was losing the pump after every second winter. I thought about taking the pump out each year and storing it somewhere inside over the winter. The boat was covered on the trailer with the drain plug removed each winter.

Sorry if I hijacked the thread.
 

seasick

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That failure rate is not normal for the pump. If I were to do one thing, it would be to fully drain the system and refill with new fluid. Perhaps the current oil is contaminated ( does the pump possible get water in the reservoir) That could kill it also if water is getting into the oil.
Make sure you use the correct oil. You can check your manual but in general regular automatic transmission oil can be used
 
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