Use of Trim Tabs
Moderators: BeaconMarineBob, Moderator, BeaconMarineDon
- The Dog House
- Active User
- Posts: 807
- Joined: Mon Jan 09, 2012 6:51 am
- Location: Bordentown, NJ
Use of Trim Tabs
I currently start to plane with my trim tabs up and then lower the trim tabs to help get my F26 out of the hole. Would it be better to start with the trim tabs down? Are there any disadvantages to starting with the trim tabs down? The F26 with the Chrysler 318 (225 hp) is definitely underpowered and needs to have the trim tabs down in order to plane efficiently. How are other F25 and F26 owners using their trim tabs?
1993 Sea Ray 200 Overnighter OB with 1993 Mercury 150 hp Outboard
1979 Starcraft 14' Rowboat with 2011 Mercury 9.9 hp Outboard
Former boat: 1971 Trojan F26
1979 Starcraft 14' Rowboat with 2011 Mercury 9.9 hp Outboard
Former boat: 1971 Trojan F26
Re: Use of Trim Tabs
I use mine to level me out when already up on plane. It makes the boat sit in the water level for better handling and allowing the props to be at a more efficient running angle. Otherwise, I don't think they are designed to get you on plane, rather than level you out once you get there.
-
- Moderate User
- Posts: 696
- Joined: Sun Aug 15, 2010 11:56 am
- Location: Finger Lakes, NY
Re: Use of Trim Tabs
I definitely use mine early to aid me on getting on plane quickly. I ease back as I reach plane and level out. I'm definitely stern heavy.
1991 Trojan International 10.8 Meter Express hull# 003 - 454 Crusaders
1961 Century Raven 22 - Gray Marine 327

http://s1086.photobucket.com/home/Todd_ ... hoff/index
1961 Century Raven 22 - Gray Marine 327

http://s1086.photobucket.com/home/Todd_ ... hoff/index
- captainmaniac
- 2025 Gold Support
- Posts: 1922
- Joined: Sat Apr 30, 2005 10:26 pm
- Location: Burlington, Ontario
Re: Use of Trim Tabs
If you are plodding along at 1500 RPM (8k) or slower, keep them up.
When you want to accelerate, put the tabs full down. As you advance the throttle to about 2000 RPM that will try to push the stern up and bow down as soon as you accelerate. That will help you get on plane (barely) at the lowest RPM, and maintain visibility over the bow - you will will probably be doing 10-12 knots at that RPM with tabs full down. As you accelerate beyond that speed, you can start bringing the tabs up. You can actually feel when the boat rides the most 'free' based on tab position for a given RPM. Too much tab and the boat runs slower, and has more bow steer (less control). Too little tab and you lose speed and could fall off plane as the stern drops, and have trouble with visibility from a lower station with the bow so high.
Important point : it takes a boat a second or three to respond to changes in input. Don't just mash the trim tab controls... When you want to adjust, give it a tap for 1/8th of a second to a half second, and WAIT 1-3 seconds for the boat to respond. It takes a while for the boat to respond to changes (in trim, throttle, steering, etc... this is not a car on pavement, it's a boat on water....). Then decide if you need more adjustment or not.
When you want to accelerate, put the tabs full down. As you advance the throttle to about 2000 RPM that will try to push the stern up and bow down as soon as you accelerate. That will help you get on plane (barely) at the lowest RPM, and maintain visibility over the bow - you will will probably be doing 10-12 knots at that RPM with tabs full down. As you accelerate beyond that speed, you can start bringing the tabs up. You can actually feel when the boat rides the most 'free' based on tab position for a given RPM. Too much tab and the boat runs slower, and has more bow steer (less control). Too little tab and you lose speed and could fall off plane as the stern drops, and have trouble with visibility from a lower station with the bow so high.
Important point : it takes a boat a second or three to respond to changes in input. Don't just mash the trim tab controls... When you want to adjust, give it a tap for 1/8th of a second to a half second, and WAIT 1-3 seconds for the boat to respond. It takes a while for the boat to respond to changes (in trim, throttle, steering, etc... this is not a car on pavement, it's a boat on water....). Then decide if you need more adjustment or not.
Re: Use of Trim Tabs
Trim Tabs can certainly be used to get the boat on plane faster. Think of them like flaps on aircraft and lower them before take off! This will also result in less bow rise and strain on the running gear as well.
Tom
Bennett Marine
Tom
Bennett Marine
Re: Use of Trim Tabs
+1Tabman wrote:Trim Tabs can certainly be used to get the boat on plane faster. Think of them like flaps on aircraft and lower them before take off! This will also result in less bow rise and strain on the running gear as well.
Tom
Bennett Marine
The tabs on my F-26 are always about half way down while getting up on plane and if the boat is loaded heavy in the cockpit their all of the way down. Once on plane I bring them up to find the "sweet spot" for the attitude of the boat and level ride side to side. An easy way to find the "sweet spot" is to make minor adjustments up or down to the tabs while watching the speed on your GPS. For example, once on plane I'll set the throttle at 3400 rpm and my speed will be 18 mph. I'll then bump the tabs up a bit at a time until the boat hits 20 mph. The rpms will also increase to 3500 without touching the throttle because I've also removed some of the load from the engine by setting the boat in its proper attitude.
Also, in a following sea I`ll often cruise with the tabs up and lots of throttle. This keeps the stern planted firmly in the water enhancing control.
Paul
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB
"Cruise Control" 1978 F-26HT
"No Control" 2012 9' Grand RIB