Instead of fixing the mortise lock it can be replaced with another mortise lock.
Replacing an old mortise door lock with a modern lock.
If you want to switch to a cylindrical design typical modern knobset mechanism is housed in the knobs and a cross bore rather than in a mortise or a rim surface mount lock you ll either want to leave the old mortise lock in place or glue in a block cut to exactly fill the space it occupied since otherwise the empty space would weaken the door.
If you have an older house with knobs that slip latches that are stuck inside the door or other minor problems then you should follow these instructions to remove the lock dis assemble it clean and perform minor repairs.
Place two screws from your new door lock kit in the doorjamb to hold the template in place then use the bit from your lock installation kit to drill a hole where the new doorknob will go.
Remove the screws attaching the inside face plate to the edge of the door as well as the plates on the door faces.
Pull the lock out of the edge of the door.
Replacing an interior mortise lock skeleton key with a modern lock with privacy latch press any key replacing an interior mortise lock skeleton key with a modern lock with privacy latch this seems to be one of the more popular posts on my blog.
Same issue exists regarding old holes in the door faces.
The problem with replacing the mortise with a bored cylindrical lock is that the new lock is smaller than the old and really has to be in the same location on the door as it s the strongest part of the door.
You d have to fill the mortise hole with a solid block of wood which might well entail digging out more of the door to get a good fit.
Use a screwdriver to remove all screws rather than a drill.
Once you ve removed the door lock template you have a space perfectly primed for your new lock.
Paint over the block to match the rest of the doorjamb.