The first pic shows the kingpin. And yes, if the motor is hard to turn when disconnected from the steering arm, you need to do some maintenance on the kingpin. I surmise it still moves so it shouldn't be that hard. First you need to push out the old grease. To do this you need a little heat and at the same time a full size grease gun with marine grease on it.
While warming up the kingpin try to shoot grease. You should also at the same time have someone slowly turn the motor on each side. You should see old grease coming out on each end of the kingpin. Continue to do so until you start seeing new grease spurting out and the motor is lighter to turn. DO NOT OVERHEAT THE KINGPIN, THERE IS A NYLON WASHER THAT YOU COULD DESTROY.