Its most likley the cable is frozen. What i would do is disconnect the motor from the bable and make sure is can turn freely. Then disconnect the cable from the tilt tube and make sure its free in there also. If you still cant turn it after that its the cable the only thing you can do to rectify it is to replace the cable. It can be a pain in the neck to replace because on some boats you have to yank the motor to replace it. If you do have to replace it its a great time to upgrade to a no feedback helm.
Not meaning to hi jack his thread but I think it would help him also. I have a 94 Nitro 170 DC and was thinking of going with the no feedback system. Can you elaborate on them. I looked and didn't know what I was looking at. I think the LX 700 is close. Recommend a no feedback. What I have is just the old fashion push pull single cable through the motor bracket. See what you think about it Rick
It sounds like your steering cable, I just replaced mine on a 99 640 lx w/90 HP Merc it took about 2 hrs and two people (because I did have to take the motor off, really just slide it to the side a little) Overall not a hard job and it cost me $175 for the new cable setup. Good luck and I would be glad to answer any questions if you are going to do it yourself
The difference between a no feedback system and a regular system( both rack and pinion and rotary) is the helm that the wheel attaches to. The cable and everything on the motor end is identical. The only real difference ins the NFB helm has clutches in it that eliminate the torque at the wheel. All the hookups etc are the same and installation is the same.
For what little it costs its totally worth it. It makes the boat so much nicer to drive.