I was wondering if there is such a thing as trim tabs that are "too big" on a B28. I used the thumbrules on the Bennett trim tab site and figured that 9x36 would be adequate. But I was thinking maybe 12x36 to get up on a plane a bit sooner when loaded down. That does seem a bit ridiculous for a boat that size though. Any input or recommendations from the experience on this site would be much appreciated.
Thanks,
Matt
Trim Tab Size
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Brewster Minton
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I just put recently Bennet 9X36 trim tabs on my B28 with the indicator. They work fine ! The boat is very sensitive to this trim tabs size. I would not go for a bigger size. I found out that you need trim tabs only to balance the boat when you have uneven weights on. The installation requires a lot of work. Since the transom is not flat you need to make a shim to have a flat mounting surface. I got useful instructions from CaptPatrick. Don't forget to get the indicator. It is very useful.
I have Bennetts too. I have never used them since they are not hooked up yet. Size is roughly 9 x18, but not positive. My boat gets up on plane quick with 2 people or 8 people, does not matter, and a full tank of fuel. How much power do you have? Only time I may use them once hooked up is to balance the load. Or you can just say "hey slim, move over to that side" and save the money!
Thanks for all the responses. To answer Kevin's question, I've got '99 260hp Mercuriser's. As it rides right now, it just starts to plane (w/ full tank) at around 16-17kts and ~3200rpm. Anything less and she's plowing. That seems like a bit of an effort to me. I'm hoping the tachs are off and the bottom is dirty. Or am I mistaken, as this is how I should expect the boat to perform? Either way I figured tabs would help out.
I just got the boat about a month ago, and I don't really trust the gages yet, particularly the tachs since they don't agree. I haven't really pushed her that hard for that reason. I plan on installing all new gages this winter so that I have faith in the info I'm looking at. I'm thinking of going with the Teleflex HD gages for the classic look and reasonable price. Any recommendations? I also have not seen what the bottom of the boat looks like yet. I'm assuming that a combination of a hull bottom in need of attention and my caution with pushing the rpms probably hasn't given me a real good idea of when the boat planes and what not.
Matt
I just got the boat about a month ago, and I don't really trust the gages yet, particularly the tachs since they don't agree. I haven't really pushed her that hard for that reason. I plan on installing all new gages this winter so that I have faith in the info I'm looking at. I'm thinking of going with the Teleflex HD gages for the classic look and reasonable price. Any recommendations? I also have not seen what the bottom of the boat looks like yet. I'm assuming that a combination of a hull bottom in need of attention and my caution with pushing the rpms probably hasn't given me a real good idea of when the boat planes and what not.
Matt
Matt.
It seems as though your boat is very heavy. I had 228hp 305ci Mercs in my 81 28. I would cruise at 3150rpm and get 21-22 knots all day. The boat did not have tabs, but it did not need them at speeds above 19-20 knots.
On my current 86 33, I have the stock small tabs and its pretty much the same thing. At speeds of less than 20 knots, it needs the tabs. Anything over that and it doesn't even need them except to balance an un-even load.
Of course the big difference is that the 454's in my 33 would only cruise the boat at 18-19 knots at 3200rpms. To get to the magical 20+ I'd be burning a ton of fuel. That's why I'm switching to 330 Cummins this winter. I'm figuring on a cruise of 22-23 knots.
It seems as though your boat is very heavy. I had 228hp 305ci Mercs in my 81 28. I would cruise at 3150rpm and get 21-22 knots all day. The boat did not have tabs, but it did not need them at speeds above 19-20 knots.
On my current 86 33, I have the stock small tabs and its pretty much the same thing. At speeds of less than 20 knots, it needs the tabs. Anything over that and it doesn't even need them except to balance an un-even load.
Of course the big difference is that the 454's in my 33 would only cruise the boat at 18-19 knots at 3200rpms. To get to the magical 20+ I'd be burning a ton of fuel. That's why I'm switching to 330 Cummins this winter. I'm figuring on a cruise of 22-23 knots.
Regards,
Doug L.
Doug L.
Matt,
I have the same engine that you have, Mercruiser 260 FW, but at 3200 RPM speed is between 21/23 and often even more with full tank and 5 people. Probably you have a problem with your gauges...for the trim tabs I would think twice before installing them. I have come to the conclusion that on the B28 they do not matter much.
I have the same engine that you have, Mercruiser 260 FW, but at 3200 RPM speed is between 21/23 and often even more with full tank and 5 people. Probably you have a problem with your gauges...for the trim tabs I would think twice before installing them. I have come to the conclusion that on the B28 they do not matter much.
I put tabs on my last boat and they never got in the way when fishing. A huge difference in cruising speed and economy.
I will be putting them on the 31 this year after 12 years without. The larger tank puts a bit too much weight in the back and putt'en along at a slow cruise the bow is up too high, tabs would come in handy. Soon as she is goosed up a bit more on the RPM's bow comes down and all but noise and fuel-burn is fine.
Funny it actually runs better at a slow cruise with a full belly, as the weight is further toward the center of the boat, but less then a half tank all the fuel is in the very back.
Can you put a portable tach on each engine to verify which is off and by how much?
I will be putting them on the 31 this year after 12 years without. The larger tank puts a bit too much weight in the back and putt'en along at a slow cruise the bow is up too high, tabs would come in handy. Soon as she is goosed up a bit more on the RPM's bow comes down and all but noise and fuel-burn is fine.
Funny it actually runs better at a slow cruise with a full belly, as the weight is further toward the center of the boat, but less then a half tank all the fuel is in the very back.
Can you put a portable tach on each engine to verify which is off and by how much?
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