Disconnect the steering drag link and make sure that the motor is free to turn equally both ways. With that cleared up, if you have a rack and pinion steering box the rack has probably jumped a couple of teeth. For that to happen the box is pretty old and needs replacing. The other possibilty is that you have the wrong drag link.
I am having the same problem with my Yamaha 200. The steering link is the same one I had when the boat was powered by an Evinrude 175. Does Yamaha have its own drag link separate from Evinrude? I just installed the link that was on the boat since I had it. The motor will turn all the way to the right allowing tight turns but left it does not go nearly as far. It bottoms out early so to speak. I'd love to switch to hydraulic steering but right now money is an issue.
When I installed my Yami I turned the wheel until the cables were the same coming out of the tube. I made the engine point straight and then I installed the link. If I remember the link did not want to fit so great. Is there a way to adjust the cable length or is that determined when you purchase them specifically?
