Loss of balance - what's the problem?

Kathleen,

Another thought:

Do you have Bennett trim tabs? If so the new electronic indicator control is the way to go if you don’t have one. Can add to any Bennett system…this little jewel takes a lot of the guess work out of the process or trim adjustment.
Love mine, at a glance I know exactly how the tabs are positioned.
Jay

EIC5000.jpg
 
Hi Sneaks,

I have the Lenco tabs. They are about 9 by 12 but taper and are only about 7 at the aft end.

I don't recall any strange control while using my tabs. I usually put both tabs full down for flat and moderate conditions at all planing speeds. With the throttle set the boat will attain the highest speed with the tabs full down.

I also have a Permatrim and I trim the motor 3/4 down for most cruising. This is to get the best speed at that rmp. I put the tabs full down as stated but will adjust one or the other to trim for level side to side. A passenger moving around will affect the that trim but I have never had the boat do anything dramatic.

Maybe my tabs have less affect than most.

Steve
 
Thirteen years ago I put Bennett tabs on my 22'. Mark Toland, if I recall correctly, was not too thrilled with my decision. Tabs do affect steering on plane - they create resistance. Also, if you are on plane and the tabs are being used for balance (side by side) and the tabs are not in the same position (up & down), if you suddenly come off plane, you will find things momentarily squirrely. I use tabs basically to help get on plane and for tweaking when unbalanced. A must in my judgment is an indicator to tell the operator just what position they are in so you can anticipate what may happen. As in most things, experience is invaluable when employing your tabs. While the tab travel is only several inches, they can have a dramatic effect, particularly while on plane. I try to use them as little as possible. Some folks mention WOT speed. The 90 will push the 22' around 30 mph at sea level. The 115 will push it around 35 mph. Both top speeds are really too fast for the 22' hull, in my judgment, unless conditions are ideal. My rule of thumb, the seas permitting, while on plane is to travel between 4,000 and 4,200 rpm, roughly 19-22 mph. Used with care, the benefits of tabs outweigh the liabilities - just my opinion. John
 
I'm wondering if we are using the same nominclature for "full down". I would call "full down", "fully extended". If that were the case, I would never be able to go full throttle, nor would I want to go full throttle. It would push the bow into the water. "Full up" to me would be "fully retracted", or up above the boat sole. Seems to be the possibility of how we state this. What's the consensus of views on this. Thanks, Ron
 
Hi, this is a little addition to the "lack of stability" issue. We agree that it is trim tab related and all the previous posts cover the subject nicely. We just want to add our experience with the 16 Cruiser we bought used, with power trim tabs. Using them created symptoms such as you described - rather disconcerting. On checking this out I found the left switch activated the right tab, and visa versa. That makes it hard to use them!
As an airplane pilot, I think of tabs like I think of flaps - down part of the switch makes them go down, up part for up. So I just turned the whole switch assembly over (or upside down) and that works for me. However, the typical switch assembly is marked "Bow Down" and "Bow UP", which is backwards from my installation/use, but may be right for you. Just make sure that the right tab responds to the right switch, and use little of it, in small increments. As others pointed out so well, the boat reacts to tab changes rather vigorously. Tabs level with hull at launching helps.
Al & Karen "G. S. Lollipop"
 
I'll contradict Al-

There are two ways to think about the tabs- you can set the switch to run the tab (Al's way), or you can set the switch to affect the boat.

I prefer tabs set up to affect the boat- so if you push the top port switch position, the port bow goes down. I think this is the way most tab manufacturer's wire them.

I prefer this method because I don't want to think about what the tab is doing, I want to think about what I want the boat to do. This does mean that when I push the port switch, the starboard tab activates, but I don't care, really, so long as the boat moves as I direct.

Neither way is better than the other, but one may be more intuitive to each individual.
 
Because you've all been so helpful, I just had to come back and report on our cruise yesterday...

We went out with both tanks equally full this time. And I used only the motor trim for bow to stern balancing. No trim tabs, none needed. It worked like a charm! We had a great day on the water and, as you all predicted, the boat felt much more in control. What a beautiful ride we had!

I feel sure now that, the other day, I had overextended the trim tabs and that, combined with the gas tanks being badly out of balance, caused the boat to veer left and severely affect the steering. Yesterday, with everything in balance, the steering was rock solid and it was even possible to move about the boat (carefully) without feeling like we were going to lose control.

Though I'm sure there will be much more to learn about handling Honu, I was so pleased to find that I really had bought a capable, stable boat... once I stopped messing too much with those trim tabs! Good advice from all of you about using them sparingly; and perhaps best used only to trim a bit from side to side, if at all. We took a cruise down the Columbia and up the Willamette to Portland, taking pictures of the "Bridge City" along the way. Click on Honu's album for more of that day. Thanks to you all!

Bridge_City_2.sized.jpg
 
breausaw":bvngd01j said:
Do you have Bennett trim tabs? If so the new electronic indicator control is the way to go if you don’t have one. Can add to any Bennett system…this little jewel takes a lot of the guess work out of the process or trim adjustment.
Love mine, at a glance I know exactly how the tabs are positioned.
Click to expand...

I was talking to my rigger about this control for my 22 and he is concerned that it needs to be mounted back by the pump and that the connections are not protected from water. I am not sure his concerns are valid but I would like to know more about how you have yours set up.

Thanks,
Warren
 
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