Disconnect cable from motor. Does the motor now move freely?
If not, the problem is on the motor.
Disconnect cable from steering helm. Does it turn freely?
You can grease the cable end and the helm, but it is likely the 30 year old cables. They fray, rust, and bind inside the casing.
Replace them.
Often times you can find a deal on the helm, the steering wheel, and the cable, for not much more $$$.
