Question on Outboard 650 Mercury Locked up at engine

[SmithCraft64]

What causes the Mercs to lock up the steering at the engine? I disconnected the control arm at the engine. I would think it should turn manually but it won't? Is there a lock I'm not seeing? Have they been known to have a problem internally? It will tilt but won't pivot.

This is a correction in my post. The engine wont turn (steer). It seems to be locked by a mechanical problem. The steering wheel is disconnected at the engine. The shifter and throtle are still connected. I can't physically turn the engine in either direction. Can anyone advise me on this? Or point me in the direction of an online manual. I don't want to purchase the boat if the engine is really messed up because of this problem. The boat needs major work. If the engine is in unrepairable condition it would make the purchase unaffordable. 65hp merc 650 engine #1647855.
thanks ahead of time.

[SmithCraft64]

Ok well it turns out that the owner somehow jammed it. Then took his winch to it and tried to free it up. My quess is that its now a couple of teeth off on the differential. And time for me to look for another engine. oh well. SmithCraft64

[SmithCraft64]

Well I guess being that I'm as stubborn as a mule. I purchased the SmithCraft and went to work.I dove into the problem a little further and figured it out. What was wrong with this engine was that it wasn't maintained obviously. The things that were not functioning were the steering tube and the pivot arm. The pivot arm was never greased at least not since it's production in the 60's. The steering tube was in pretty close to the same condition. Except the cable snapped inside at its connecting point. My guess is from trying to force the unlubricated pivot arm to move via the rack and pinion steering. Which was frozen and couldn't be moved even with a winch. The job was to tear it down and free up the arm. To do so I lifted the engine off the transom with my cherry picker then removed the arm from the engine at the mounts put it in my vice applied some penetrating oil to it and let it soak overnight. Then carefully started trying to work it back and forth with some help from the leverage of a cheater bar. To no avail. I then tried heating it with a low flame from my torch. After quite a few trys I got it to free up then disasembled it added a new zert fitting, honed it with emory paper removing the rust and corrosion and reasembled it. Works like a champ. Now im in the process of getting the engine ready to start.Yes the engine thats been sitting for ten years. to be continued.... I'm also stripping the old rotted wood out of the hull down to the aluminum and starting fresh from that point up. I'll post on its progress soon. Any recommendations on the restoration would be most appreciated. thanks, SmithCraft64