Unusual problem with security screen door lock

[jonwil]

I have this lock on the security screen door of my apartment:
http://www.cncmods.net/files/lock2.jpg
When you close the door, the little nub near the top of the picture is pushed in and that releases the bolt. What is then supposed to happen (and was happening until earlier today) is that when you open the door, the little nub is supposed to pop back out and retain the bolt so its held back (as seen in the picture).

But whats going on now is that the little nub wont push back out and the bolt wont get held back. I have to jiggle things a lot to make the nub pop out and the bit that holds the bolt back activate and hold the bolt back.

Anyone out there know how one of these sort of locks are supposed to work, what the mechanism would look like or how I might be able to sort this out?
The key (in both keyholes) and the locking snib both work just fine, its just the little nub that wont pop out correctly unless I jiggle and bump it a bit to make it pop back out.
Preferably looking for an answer other than "replace the lock" or "call a locksmith"

It doesn't render the lock useless, its just really annoying

[smokingman]

Clean and lubricate?
Worth a try.

[jonwil]

Somehow without me doing anything to it, it seems to have started working again.

[1mrchristopher]

In that case, definitely clean and lubricate.

[MrWizard]

Generally that little nib is called a deadlocking mechanism. It isn't to hold back the spring latch until the door is shut. It is suppose to make the spring latch not to be able to be pushed back when the door is shut so it cannot be opened by sliding something between the door and frame to push that spring latch back. Try it see what happens with the door open and hold that nub in all the way you should not be able to push the spring latch in. If it really works like you say that would be a very strange operation for a mortise lock.

[MisterPhi]

In Oz, this is a Whitco MK2 screen door lock. The 'nub' is a bolt retaining device used to hold the bolt in a half extended/sprung loaded position. This allows for the lock to be fitted on both left and right handed doors(note the double sided angle on the bolt face). When the door is shut and the nub depressed the bolt is extended twice it's length and deadlocks into the frame strike. This unit is pressed sealed and usually unserviceable other than a truck load of wet lubricant. This is 9/10 times the way to go . Happy locking.

[billdeserthills]

I have this lock on the security screen door of my apartment:
http://www.cncmods.net/files/lock2.jpg
When you close the door, the little nub near the top of the picture is pushed in and that releases the bolt. What is then supposed to happen (and was happening until earlier today) is that when you open the door, the little nub is supposed to pop back out and retain the bolt so its held back (as seen in the picture).

But whats going on now is that the little nub wont push back out and the bolt wont get held back. I have to jiggle things a lot to make the nub pop out and the bit that holds the bolt back activate and hold the bolt back.

Anyone out there know how one of these sort of locks are supposed to work, what the mechanism would look like or how I might be able to sort this out?
The key (in both keyholes) and the locking snib both work just fine, its just the little nub that wont pop out correctly unless I jiggle and bump it a bit to make it pop back out.
Preferably looking for an answer other than "replace the lock" or "call a locksmith"

It doesn't render the lock useless, its just really annoying

Since You don't own the door or the apartment call your landlord, or the maintenance dept. to fix it

[Jburgett2nd]

Since You don't own the door or the apartment call your landlord, or the maintenance dept. to fix it

The maintenance people in my apt. complex are about as handy as a monkey that cartwheeled across a landmine. They managed to put the door on the hinges crooked and completely mess up the weather strips, when I asked if I could just fix it myself they said that would violate my lease agreement. Not saying this guys maintenance will be shoddy but mine certainly is.