Last Monday I launched my NTM 1984 Larson and discovered that it doesn't steer well. This is my first sterndrive but I have had outboards before. My friends helped me adjust the anode trim tab and I thought we had it about right. It steered fairly well the next day. Then on Wednesday it started pulling to the left again. I turned the trim tab a little to the left and it was working fairly well again. Then today I take it out for a spin and it pulls to the left again no matter what speed or trim. I've never had this issue with outboards. What is going on??? Any ideas??
You don't say what engine you have, but I assume it is a 4 cyl without power steering. You also didn't say if the tab was staying adjusted or coming loose & moving after you set it.
You have the concept correct, move the aft edge of the tab towards the direction the boat (steering) is pulling.
You will notice with an I/O that the steering torque is affected by trim angle & RPM. That being said, you need to find the optimum cruising speed & trim that you feel comfortable with and then adjust the trim tab to null the torque.
There will be no way to adjust the tab for cruising speed and not have torque with high speed/high positive trim angle runs. For that you will need power steering.
Thank you for the reply. After pulling the motor up out of the water I could see that the tab was coming loose. I again set it to the left and tightened it down as hard as I could and went out into some very windy conditions. It steered okay on that run but I now understand the affect trim and speed have on the steering. I also understand why they offer power steering! I guess I'll just have to get used to it. Thanks again.