Help with this mortise lock

[BobbyG06]

Hi everyone,

I'm new to the forum and I'm having trouble with this door latch and lock. The door latch does not retract into the mechanism when the door is shut. I can manualy push it in and it works, and can also push the thumb latch down and it will work that way also, but it will not shut on its own. I made sure the striker plate on the door frame is making contact with the angled side of the latch bust it still will not retract. I removed the lock and opened it up to see if I can see if something is broke, but everything looks like it is working. I don't know much about locks, but just by looking at it, it looks as if everything is ok. Any ideas would be appreciated.

[cledry]

If you can push it in manually then the strike should also be able to do the same. That thing is ancient.

It has to be in the relationship of the strike to the latch, look for any shiny spots, make sure there are no burrs. Everything looks OK inside though.

[2octops]

File, sand and polish all that corrosion off the moving parts inside the lock body and lubricate it with white lithium grease. It should work very smooth after a good cleaning.

[MisterPhi]

You could also chech for wear on the mount/faceplate where the latch projects from the body.if there is room for movement the latch will bind with horizontal pressure.file both surfaces smooth and grease. Happy lockings.