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View Full Version : Trim Tabs For Outboard Sixteen



Nat Bozarth
04-22-2003, 09:52 AM
Anybody know about pros and cons for trim tabs on a 16 outboard? How big should they be and where on the hull? Never had an outboard before and boat wants to hook hard left on re-entry at speed in moderate chop and above.

Forrest
04-22-2003, 09:59 AM
Most 16 Donzis use the smallest Bennetts or Boat Leveler tabs which are, I believe, 12" wide. They are usually mounted about 1/2 aboveteh bottom just inside the chine. Before that, make sure that your steering is tight and you don't have any major hooks in the hull. Also what prop are you running?

Turks and Caicos Islands! Now that's the place to have a Donzi!!!

MOP
04-22-2003, 04:55 PM
Sounds like you are jumping it clean out of the water, when it lands the first thing to grab is the prop and it wants to go both forward and side ways doing a little prop walk. Tabs won't help that but will improve the boat in other ways.

Nat Bozarth
04-24-2003, 09:43 AM
Forrest, I'm just breaking in a tuned and balanced 175 OMC that should be making about 200 hp and have just started the prop game with a 22 pitch raker. seems to have an awfull lot of bow lift and not huge rpm but I am not really looking for much rpm yet with only 4 hours on the motor.

Thanx

Nate

MOP
04-24-2003, 06:04 PM
Nate what is your WOT RPM now? I worked on those buggers for 30 some odd years, make sure you are up in the band early 5's is good. Is it a looper or cross flow? If its a cross flow, the 235 exhaust plates the big humped one will give you another 8-10hp. There is one out here motor up on third hole with a cleaver, I think I can get in touch with the guy, if I do I'll get his number.

Forrest
04-25-2003, 10:51 AM
Yea MOP, I was thinking that a cleaver (no bow lift) may be worth a try, or some prop in between a Raker and a cleaver in terms of bow lift. You probably don't need all that bow lift a that Raker prop gives.

CrackerJack
04-25-2003, 11:09 AM
I have a 16'I/O and installed Lenco trim tabs about 1 year ago. They have been in salt water numerous times and fresh water alot this year.
I have not had any problems with them and they still look like new. Installation is very simple and easy.

MOP
04-25-2003, 06:23 PM
Lenco and Bennets are both very good, I was leary of the Lencos at first being electric but they seem to be doing very well. I'll still use the Bennets for a few more years. I've seem alot of real old Bennets with no problems. No not as old as me!

Nat Bozarth
04-26-2003, 11:10 AM
Hi. M.O.P. , The motor was a stock Ocean Runner, loop charged and since balanced and ported etc and runs incredibly strong but again early stages of its life. The engine is on a Jack Plate but I do think the prop is providing too much lift and as Forrest said I need to go more the cleaver route. Its a little hard to play the prop game here being I have to import everything so any advice would be appreciated. I ordered a set of Bennet sport tabs 12in by 9in so we'll see what happens. Have also found a slight deppression ending in a hook to the very back of the hull about 6 inches to the right of the centerline. Would this heel the boat in the opposite direction?

Than in advance

Nate

Nat Bozarth
04-26-2003, 11:11 AM
Hi. M.O.P. , The motor was a stock Ocean Runner, loop charged and since balanced and ported etc and runs incredibly strong but again early stages of its life. The engine is on a Jack Plate but I do think the prop is providing too much lift and as Forrest said I need to go more the cleaver route. Its a little hard to play the prop game here being I have to import everything so any advice would be appreciated. I ordered a set of Bennet sport tabs 12in by 9in so we'll see what happens. Have also found a slight deppression ending in a hook to the very back of the hull about 6 inches to the right of the centerline. Would this heel the boat in the opposite direction?

Than in advance

Nate

MOP
04-27-2003, 07:04 AM
I think a small depression will not cause healing, might just cause some turbulance and not have any effect on speed. If it was a longer section then it would probably have some effect. Where is CDMA he is our flow engineer!

MOP
04-27-2003, 07:40 PM
Poodle he has a depression close to the keel, the little hook in the 16 is outboard and for the most part clear of the water running. Nate you can get that dimple out with a heat lamp if you can get at the inside to be able to apply constant (blocking or what ever) pressure after heating. It takes a little time, don't get the lamp any closer than 12-14 inches from the hull. Never let the heat get more than your hand can stand move the light if need be. About an hour you should be able to apply pressure and get it out, make sure you let it cool several hours before removing blocking or what ever you used. If its not all gone repeat with a little more pressure, some time I push stuff a tiny bit past true it depends. Make you blocking stuff up ahead of time and make sure you can make easy adjustments, hard wood wedges work very well. You can use most anything. I have used load jacks and heat to push a sail boat back into shape, You can strighten some pretty bad stuff. Send me mail with an inside and outside shot, I can give you some ideas.