adjusting trim fin on anti cavitation plate

[aerobat]

hi !

when approaching lowest gliding speed my steering gets stiff and you need to hold the steering wheel, otherwise it would by itself turn to the right. at trolling speeds as well at high speed the steering is easy - so i played a little with the trim tab at my outboard ( evnriude ficht 150 ) . it was set at 4deg right - it seems to be the maximum adjustable. i resetted to 2 deg right with nearly no effect.

when i understand correctly - when the steering tends to move to the right you have to give more right trim on the tab and vice versa, correct ?

do you also have a stiff steering at the threshold between displacement and gliding speed ?

thanks for any inputs !

 

[JimS123]

Re: adjusting trim fin on anti cavitation plate

Yes, if it steers easy to the right (in other words its hard to turn left). then turn the trim tab to the right.

Trim tab effect is influenced by the speed you run at, plus the trim angle of the motor.

Soooooo. pick the speed and trim you most often run at, and adjust the tab accordingly. However, you will have to expect that it may not be prefect at other speeds.

 

[Rocky_Road]

Re: adjusting trim fin on anti cavitation plate

hi !

when approaching lowest gliding speed my steering gets stiff and you need to hold the steering wheel, otherwise it would by itself turn to the right. at trolling speeds as well at high speed the steering is easy - so i played a little with the trim tab at my outboard ( evnriude ficht 150 ) . it was set at 4deg right - it seems to be the maximum adjustable. i resetted to 2 deg right with nearly no effect.

when i understand correctly - when the steering tends to move to the right you have to give more right trim on the tab and vice versa, correct ?

do you also have a stiff steering at the threshold between displacement and gliding speed ?

thanks for any inputs !

It is real simple, but seems to be illogical: but, you move the TRAILING edge of the trim tab in the direction that the boat wants to 'pull'. In other words, if your boat wants to pull right (starboard) you turn the back edge of the trim tab to the right. This forces your outdrive, or outboard, to want to turn your boat to port and you eliminate your problem.

Like suggested, you will not find a perfect spot...but should focus on correcting the torque steer in the range that you most use your engine (idle, cruise, or WOT).

Happy boating!