Add a lock to this door

Hello! I think the 82-086 has a good chance of working for you, yes. My only reservation is the thumb latch position. Note that the thumb latch on the 82-086 is fixed in the lower position. Your old one seems to be in the lower position, too, but you should check just to make sure.

The 82-086 also already comes with a key lock, there's no need to purchase the 82-315 separately.

If you only wanted to add a key lock to your existing handle, then the 82-315 is your best bet. My reservation here is that I'm not sure if you have the room on your exterior handle to install it. You may be safer buying an 82-044 exterior handle as well.

Your mortise latch should have a top hole on the side for that binder post to slip through. It definitely shouldn't be sticking out of the door like that. Take a look at the 82-243 mortise latch as an example and examine our pictures for it. You can see the hole I'm talking about at the top side of the lock. Check to see if your existing mortise has that same hole.

That's not something I can say for sure, since I don't know if your mortise is a special kind or not. I can only tell you that that nut is specifically designed to go through most kinds of mortise holes. You may want to remove the mortise from the door and try to "install" the handle through it to see if you can eyeball exactly what's going wrong. Let me know what you come up with.

What you need is a "Thru-Bolt". I would suggest taking the fasteners you now have to a hardware store in your area. They should be able to give you the one you need for your patio door. Normally what I would do would be to open up the hole with a rat tail file to install the handle if I came across this problem.