Replace mortise style handle and lock

[Great White]

We have a mortise style handle and lock on the storm door leading to our balcony. Recently the lock failed and now the thumb latch turns round and round but the deadbolt won't retract. I have removed the two bolt screws from the face plate but the face plate won't come off as the thumb latch is in the way. There is no set screw on the thumb latch or any other obvious way to remove it. Even if I could remove the face plate I don't see anything behind it that will give me access to the lock. All the tutorials I can find for removing similar handles all seem require access to to the outside and/or side of the door but that isn't practical in this case as the door is locked shut and this is a 3rd floor balcony. I am assuming the lock will have to be drilled out but I'm not exactly sure how to do that and I thought I would check here before trying something that drastic.

 

[KenGMac]

The "Thumb Turn" is almost invariably held in place by a set screw inserted from the edge of the door, hence there are no "obvious" fixings when the door, as it is here,closed and latched. A lot of the ones I have seen the set screw passes completely through the locking mechanism and into the hidden internal metal frame of the door

Can I suggest??? you try and tap the thumb turn lightly with a hammer to see if the dead bolt will reengage.

To remove the face plate, the actual thumb turn will probably need to be removed.

Ken.

 

[Great White]

The "Thumb Turn" is almost invariably held in place by a set screw inserted from the edge of the door, hence there are no "obvious" fixings when the door, as it is here,closed and latched. A lot of the ones I have seen the set screw passes completely through the locking mechanism and into the hidden internal metal frame of the door

Can I suggest??? you try and tap the thumb turn lightly with a hammer to see if the dead bolt will reengage.

To remove the face plate, the actual thumb turn will probably need to be removed.

Ken.

Tapping with a hammer worked! It didn't fix the lock completely but enough to get it open.

Thanks Ken!