My front door mortice lock is jammed, locked. On using the key, it will turn part way, perhaps almost halfway, then comes against a block and will go no further. I have tried wiggling the key about from inside and outside, to no avail, and WD-40 squirted in the keyhole hasn't worked either. How can I get the door opened to replace the lock?
jammed mortice lock
- Thread starter agb
- Start date
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Ok. Chubb 3K74 or 3K75.
Perhaps take the handles off and see if the lock has been drilled open before.
If none of the keys have Chubb embossed on them then you do not have original keys.
Can you feel any levers lifting when the key is inserted and turned. If the levers are being lifted you should feel some resistance and the key spring slightly back?
What is that I can see through the key hole, how about take the handle off and another photo lined up with key hole.
Did you try the rattling the door trick?
DC
Teamlocksmiths
Perhaps take the handles off and see if the lock has been drilled open before.
If none of the keys have Chubb embossed on them then you do not have original keys.
Can you feel any levers lifting when the key is inserted and turned. If the levers are being lifted you should feel some resistance and the key spring slightly back?
What is that I can see through the key hole, how about take the handle off and another photo lined up with key hole.
Did you try the rattling the door trick?
DC
Teamlocksmiths
A Chubb 3K74 (which it looks like) is a very strong and reliable lock.
I too think that the bolt is probably prevented from withdrawing by being jammed in the staple (keep), probably because the door has dropped and the bolt is pressing downwards in the frame, or possibly warped and jammed on the side. So jigging the door about while you apply moderate pressure to the key may help it come free. Do not lock it again until you have worked out where it is jamming and eased it. If this is in fact the cause, you may find the brass bolt of the lock is rubbed shiny at one point.
BTW your key looks very worn, and is also a copy, so may not be a good fit. If you have any spare keys, try them. Attempt from both sides of the door. It might help to give the key a "lift" so that it is pressing slightly upwards in the lock.
Did it slowly become more difficult to lock and unlock, or go wrong suddenly?
If this fails, can you lay your hands on an angle grinder?
I too think that the bolt is probably prevented from withdrawing by being jammed in the staple (keep), probably because the door has dropped and the bolt is pressing downwards in the frame, or possibly warped and jammed on the side. So jigging the door about while you apply moderate pressure to the key may help it come free. Do not lock it again until you have worked out where it is jamming and eased it. If this is in fact the cause, you may find the brass bolt of the lock is rubbed shiny at one point.
BTW your key looks very worn, and is also a copy, so may not be a good fit. If you have any spare keys, try them. Attempt from both sides of the door. It might help to give the key a "lift" so that it is pressing slightly upwards in the lock.
Did it slowly become more difficult to lock and unlock, or go wrong suddenly?
If this fails, can you lay your hands on an angle grinder?
Thanks to DC and John D for their responces
I have found an original key - it is a Chubb and a photo is in the album jammed mortice lock 2 This original key does not unlock the door. Also I have posted a photo after I have removed the handle. Grateful if Mod3 could get these from album up onto topic page.
On zooming in on the photo with the handle on I have established what appears inside the keyhole is actually a reflection from the other side of the keyhole.
With another mortice lock I have (Chubb again I believe), when unlocking there is steady pressure when the key engages for half a turn, then it unlocks. With the jammed one, there is no, or very slight resistance, for a quarter turn, then a complete block.
Wiggling the door when turning the key did not work
I do not believe the door has dropped and the bar trapped. This problem occurred out of the blue with no previous problems with the lock
View media item 19946
View media item 19945
I have found an original key - it is a Chubb and a photo is in the album jammed mortice lock 2 This original key does not unlock the door. Also I have posted a photo after I have removed the handle. Grateful if Mod3 could get these from album up onto topic page.
On zooming in on the photo with the handle on I have established what appears inside the keyhole is actually a reflection from the other side of the keyhole.
With another mortice lock I have (Chubb again I believe), when unlocking there is steady pressure when the key engages for half a turn, then it unlocks. With the jammed one, there is no, or very slight resistance, for a quarter turn, then a complete block.
Wiggling the door when turning the key did not work
I do not believe the door has dropped and the bar trapped. This problem occurred out of the blue with no previous problems with the lock
View media item 19946
View media item 19945
Found the other pictures in your album.
Chubb 3K75, drab olive green colour. Not battleship gray. I thought perhaps that the lock case cover had become undone and had moved away from the lock case but the curtain (thats the part the key goes in) seems to be OK, but try tapping the lock case does it sound or feel loose.
Sure it the correct key (I know but it does happen).
DC
Teamlocksmiths
Chubb 3K75, drab olive green colour. Not battleship gray. I thought perhaps that the lock case cover had become undone and had moved away from the lock case but the curtain (thats the part the key goes in) seems to be OK, but try tapping the lock case does it sound or feel loose.
Sure it the correct key (I know but it does happen).
DC
Teamlocksmiths
There are only a certain number of things that can be causing your problem and I think that if your convinced that the bolt is not jammed and the correct key is being used then I (and I do this for a living) would be drilling into the lock case to manipulate the bolt back. JohnDs suggestion of removing the hinge pins is a good suggestion and the least demanding of technical skills.
Or bite the bullet and call a local locksmith. Beware of any national company, ask friends/relations for a recommendation.
Please let us know how it resolves itself.
DC
Teamlocksmiths
Or bite the bullet and call a local locksmith. Beware of any national company, ask friends/relations for a recommendation.
Please let us know how it resolves itself.
DC
Teamlocksmiths
Just had another thought.
Are you sure that the bolt is not already back (unlocked) and the door will not open because the upper roller bolt is not being retracted by the handle. This would make sense of your description of where the key is stopping.
If you can slide a very thin piece of plastic or cardboard between the door and frame below the lock and lift it up and see where it stops you can prove or disprove if the bolt is in or out. If the bolt is out your piece will stop just about level with the top of the keyhole. Unlocked and it will come up to about half an inch below the hole for the handle.
DC
Teamlocksmiths.
Are you sure that the bolt is not already back (unlocked) and the door will not open because the upper roller bolt is not being retracted by the handle. This would make sense of your description of where the key is stopping.
If you can slide a very thin piece of plastic or cardboard between the door and frame below the lock and lift it up and see where it stops you can prove or disprove if the bolt is in or out. If the bolt is out your piece will stop just about level with the top of the keyhole. Unlocked and it will come up to about half an inch below the hole for the handle.
DC
Teamlocksmiths.
If you got nothing to lose then get a pliers and turn the key with a bit extra force, you may get away with it. Doesn't seem much of a gap between the frame and the door, it could be the bolt latch is rubbing on the frame latch, maybe a crowbar to lift the door up slightly and turn the key
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