I have funky steering on my boat. It has really tight spots in it and can get pretty hard to manuver and you really have to man handle it. I was thinking steering cables.
They are pretty much wear items. Try disconnecting it from the drive and see if it's easier to turn, that will let you know if it's the cable/helm or something in the drive. Probably cables.
If it were cables, would that make everything hard to turn by hand? What I mean is if I am outside the boat and grab the drive, it is very hard to move side to side by hand.