Adjusting Trim Tab

[legalfee]

I've got a 1996 90hp that pulls hard to the right. I've read adjusting the trim tab can help this.
How do I go about it? Thanks!

 

[Stinnett21]

The geometry of this situation is hard to discuss in text but here goes. If you mean when letting go of the wheel the boat wants to turn right then adjust your trim fin so that it pulls the trailing end of your motor back to center. That would mean when standing behind the motor turn the fin so it points to the left. Putting it another way if you stand over top of the fin turn it so it's at a 10:00 o'clock, or so, position.

 

[legalfee]

The geometry of this situation is hard to discuss in text but here goes. If you mean when letting go of the wheel the boat wants to turn right then adjust your trim fin so that it pulls the trailing end of your motor back to center. That would mean when standing behind the motor turn the fin so it points to the left. Putting it another way if you stand over top of the fin turn it so it's at a 10:00 o'clock, or so, position.

Makes sense. The opposite of what you would think though.

 

[jerryjerry05]

When you pull to the right, your supposed to turn the fin to the right.
When you put the boat in the water, everybody out of the boat see if it sets level in the water.
Some cases they load up the twin batteries they end up on the drivers side and this can cause problems.

 

[legalfee]

When you pull to the right, your supposed to turn the fin to the right.
When you put the boat in the water, everybody out of the boat see if it sets level in the water.
Some cases they load up the twin batteries they end up on the drivers side and this can cause problems.

The boats sits level in the water (24 ft Sylvan pontoon). The battery is in the middle and 20 gallon gas tank is on the port side.

 

[racerone]

When you are behind the boat you turn the fin to the right , if boat takes off to the right.

 

[dingbat]

A boat will pull hard to the right if not trimmed properly as well.

If your running neutral trim or lower, trim up a bit and see if it dissipates at all.

 

[jerryjerry05]

A boat will pull hard to the right if not trimmed properly as well.

If your running neutral trim or lower, trim up a bit and see if it dissipates at all.

That's what the fin is supposed to stop. Right handed props will always pull right.

 

[Stinnett21]

When you are behind the boat you turn the fin to the right , if boat takes off to the right.

I believe this is right. I told you wrong above. So try it in a 1 o'clock or 2 o'clock position. I'm trying to remember back to my outboard days. I do remember trim made a big difference. The goal is get the wheel steady when you're at normal cruising speed and trim setting.

 

[jerryjerry05]

You should be able to release the wheel while underway, not while accelerating.

 

[dingbat]

The tab simply creates drag opposite prop rotation. It’s only effective for the speed and trim you set it for. Works great for a motor w/o trim and tilt.

You can dynamically counter prop torque by adjusting your trim angle.

Trim down increase torque steer, trim out far enough and the prop will actually start pulling to the left......the secret is to hit that sweet spot right in between where prop steer goes neutral.