Listing to the left

jd_smith

Cadet
Joined
Oct 26, 2003
Messages
24
Hello everyone, <br /><br />I recently had an 86 Johnson 140 installed on my 19.5' Bayliner and when under power the boat lists to port, the faster I go the more it lists. Would trim tabs correct this problem?<br /><br />Thanks, <br /><br />Justin
 

hohmanr

Seaman Apprentice
Joined
May 3, 2002
Messages
36
Re: Listing to the left

While I would imagine trim tabs would rectify the list, it wouldn't solve the root cause...Sounds like the engine was installed improperly or your carrying too big a cooler along....<br /><br />Sounds like you need to determine the real issue here...Trims tabs would be a real hassle because the degree of list changes as well...You would be forced to drive with one hand on the wheel,one hand on the throttle and one hand on the trim tab switch...
 

jd_smith

Cadet
Joined
Oct 26, 2003
Messages
24
Re: Listing to the left

Thanks for the info but I can't figure out why the boat leans so much. It sits fine in the water and the motor appears to be mounted correctly. What else could cause this? The boat does not leak at all and I just repainted the hull, any thoughts?
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: Listing to the left

Individually adjustable tabs will correct the problem.<br /><br />Does the steering pull when under way? If so adjust the trim tab.<br /><br />You can check the mounting of the motor by measuring the width of the transom. Your motor should be centered.
 

JHOLE

Seaman Apprentice
Joined
Dec 6, 2002
Messages
48
Re: Listing to the left

I am with these guys on this one. The easy place to start is the motor trim tab. Just a thought, is the motor mounted at the right height? ( Cav plate just under keel ) IMHO-I would find the real problem not install tabs as a fix for something else that's wrong.
 

Jdeagro

iboats.com Partner
Joined
Jul 30, 2003
Messages
1,682
Re: Listing to the left

jd - Smith<br /><br />A list to the port side on a single engine boat is most likely caused by the torq of the motor (torq list). When the motor rotates in one direction (clockwise) the boat wants to rotate to the opposite direction (counter clockwise).<br /><br />This is also why most helms are set to the starboard (right) so as to counter balance the list.<br /><br />There are some things that can exaggerate the list, such as agressive props and hydrofoils.<br />The props with an agressive cup will create more torque and increase the list.<br /><br />Hydrofoils will increase the stern lift and concentrate this lift in the center of the boat (since it is attached to the motor) which reduces the stability port to starboard like a teeter totter. Lifting the boat from the center is not advisable. Secondly, hydrofoils provide increasingly more liftas the speed of the boat increases, which creates excessive stern lift and bow pressure when cruising. With the extra bow pressure the boat will have a tendency to bow steer" and exagerate the torq list.<br /><br />As others have said, find the problem first, then determine the solution. If the motor is mounted correctly ( height should place the cavitation plate at the same level as the bottom of the boat - bottom edge of the keel if it is a V design) plus or minus 1". If you have a hydrofoil on the motor, remove it and see if the problem is eliminated or minimized. <br /><br />If all of the above is OK, then the list is likely a simple torq list, and can be corrected by trim tabs. Given that the list increases and decreases with speed, i would agree with others that manualy controled tabs could be somewhat of a nuisance if they need constant adjustment. <br /><br />Smart Tabs are a self adjusting trim tabs system that requires no driver control. The system reacts to the water pressure when underway. It is constantly active. They are adjustable upon installation and can be set to correct a torq list or any permanent list.
 

airman

Petty Officer 1st Class
Joined
Aug 9, 2003
Messages
332
Re: Listing to the left

I have a set of manual control tabs (Bennetts) on my boat. I love 'em. I have a tall, top-heavy boat and she really leans in on a turn. If I kick the inside tab down as I go into a turn the boat turns way tighter and flatter. There are definitely some good traits of the Smart Tab system but I really love the precise, on-the-fly control of an electric tab. The constant adjustment really isn't an issue unless you contantly change speed. I don't normally touch them until I get to cruise speed and then I set them where I like. I also don't think anything but a manual tab could give me the control I want in a turn. The one real advantage I see to the Smart Tabs would be the active shock dampening they could provide. And the cost, of course.
 

Jdeagro

iboats.com Partner
Joined
Jul 30, 2003
Messages
1,682
Re: Listing to the left

airman;<br /><br />I would agree with you in your case. If the boat has a high profile or tower or is used as what we call a "destination" boat (larger boat cruising from point "A" to point "B") helm controlled tabs could provide more control. If the correction requires maximum lift on one side to correct the leaning, then the choice is simple - helm controlled tabs. If the boat is in the 22 ft and up range ( actual hull length and more than 9 ft wide) use helm controllled tabs. Bennett is a very well established company with excellant customer service.<br />If the boat is under 22 ft, trailerable, and used for water sports, joy cruising, or fishing Smart Tabs will provide excellent performance, ride and handling improvements, including the correction of a torq list.
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: Listing to the left

Also, Make sure that motor is installed DEAD CENTER on the transom...
 

mellowyellow

Vice Admiral
Joined
Jun 8, 2002
Messages
5,327
Re: Listing to the left

a cup or a bow in the hull can cause this, but<br />most likely one of the fixes already mentioned.<br />good luck,<br />M.Y.
 

jd_smith

Cadet
Joined
Oct 26, 2003
Messages
24
Re: Listing to the left

Thanks very much for the info! Looks like I'll be getting some Smart Tabs before next season!
 
Top