Trim tab

[regency01]

Boat steers easily to the right but takes Some force to steer left. I have a 14' tri hull with a 25 mariner with stick steering. I was told to adjust the trim tab. True or False? Which way does it need to turn (the trailing edge left or right) to reduce the left force?

Thanx
Rick

 

[WillyBWright]

Re: Trim tab

Looking from behind, the tab on most outboards should be slightly askew to the right.

 

[MikDee]

Re: Trim tab

On most boats with a right hand prop rotation, (as looking at it directly from the rear) the prop torque will make it easier to turn right, you are fighting the motor turning left, especially at speed. The tab should actually be moved to the left, so that as your boat moves through the water, (especially on plane) it will exert a force to the left (like a small rudder), slightly counteracting prop torque. Move it in small increments to find the best spot, bu be aware when you come off plane, the boat will slightly abruptly, pull a bit to the right.

 

[regency01]

Re: Trim tab

Thanks for your replies, but I have a: turn it right and a: turn it left. Can you all clarify this a bit more? Thanks to all.

 

[MikDee]

Re: Trim tab

Ok, I know it's abit confusing, but here I can't make it any clearer, pretend it's a little rudder, turn it so that the back edge of it is to the left of center, will make your boat go to the left, counteracting prop torque (I guess you might say the front edge of it, would go to the right - WillyBWright) there is usually small marks on the cavitation plate to use as an index of how far you went, or how far you want to go.

 

[regency01]

Re: Trim tab

Thanks, I think I understand now.

 

[studlymandingo]

Re: Trim tab

Does it only steer harder when underway, or is it hard to steer at idle as well?

If it is only while you are underway, then the torque tab will help; if it is always a little sticky, then you need to be looking at your steering tube and other steering components.

Conversly, I installed hydraulic steering, and difficult steering is a very faint memory.​