New lower unit

[nickatnight]

Have a new lower unit but the old trim tab, best place to put trim tab to start. I know it will need adjusting but where does one start?

 

[Edchris177]

it helps to identify what power plant you are referencing.
I had a I/O Merc, book says centered, as I had power steering. Same with my current Volvo stern drive.
If it’s an outboard, put it in the same orientation as the old one was.
Loosen the steering friction & try it. If torque wants to turn the steering, adjust in small increments. Visualize a rudder, (which is your lower end), with a trim tab sticking out. Then visualize water flow…moving the tab will trim the motor in the opposite direction, just like rudder tabs on an airplane.

 

[nickatnight]

My mistake it's a 120hp V4 outboard. The old lower unit had indents on the bottom but the new unit does not. Was just wondering where to start.
Thanks.

 

[faztbullet]

Straight

 

[racerone]

I usually offset them slightly to the right ( starboard ) to start with.-----And if the boat veers off to starboard , you turn the tab more to starboard.

 

[nickatnight]

Thanks, one and all, that gives me a great starting point.