Residential & Commercial Security - Locks, Keys & Dead Bolts - Help with 25yr old dead bolt removal

Thanks for the help first of all. What I am dealing with is backdoor lock. Believe it is a mortise lock, all in one lock with dead bolt & door handle. Door handle is above the dead bolt. Dead bolt has key hole outside and thumb turn inside. Thumb turn broke with door shut, would only spin and spin without unlocking. I have been able to slide the latch in to open door. I have removed casing, allen wrenched out the screw to remove door handles, removed push pin from thumb turn to take that off. All visible screws have been removed at this point. Dilema, the dead bolt lock will not come apart to remove the lock casing from inside the door. I am not trying to salvage this lock, simply replace the lock. I am needing to get this apart to remove the locking. With a flashlight, I can somewhat see into the screw hole and there does not appear to be any type of allen screw, regular screw or anything of the sort to unscrew from inside the door. It is basically like the lock is stuck together. I have sprayed WD40 every which direction as well with no help. What am I missing? Jason

I'm going to presume this is an "Atrium" style door lock.

The key cylinder is probably a Euro cylinder. (teardrop shaped)

If you have the key and it wont unlock from outside, you might be best to remove the loose pin hinges to remove the door.

Calling a locksmith might be cheaper too.

The key cylinder can only come out with the door open, so you can remove a philips screw from the edge. Screw is about 2.5" long.

Without a pic...it is hard to understand your dilemna.

I have been able to get the door open and that screw out. It is a tear drop looking piece. The screw was about 2 1/2 " long and goes through the lock inside the door. However, even with that piece removed, i cannot get the lock apart?

How do I post a pic? I am not on photo bucket or anything like that. Can I email a pic to you?

Most euro cylinders require the key turned, to be able to remove the cylinder.

The cam (inside) requires correct positioning to remove the cylinder. Either have the key or have the lock cylinder picked or bumped.

Thanks for the help. Because the lock was broken, some pieces of it were keeping the lock from releasing. I had to show it who was boss. Basically had to drill into the 2.5" slot and widen the screw hole. By doing this, I was able to weaken the attached middle portion that houses the screw and break the lock in half. Now it is trying to find the replacement. I bought a 1.5" replacement but I believe I need at least 2 3/4". Off to the hardware stores unless someone knows a great online store? Thanks again for all the suggestions and helpful tips.

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