How do pop-up plugs fail?

[elmsoft]

How do pop-up plugs fail?
And more to the point. what can be done?

Using my bath to store water ( water works in the street and supply cut off) I discovered the plug allows a slow drain. No big worry, I shower rather than bath anyway. But now my basin plug won't click down!
Can anything be done about either or is replacement needed? ( I have siliconed the bath panel in place and am reluctant to remove it)

 

[durhamplumber]

How do pop-up plugs fail?
And more to the point. what can be done?

Using my bath to store water ( water works in the street and supply cut off) I discovered the plug allows a slow drain. No big worry, I shower rather than bath anyway. But now my basin plug won't click down!
Can anything be done about either or is replacement needed? ( I have siliconed the bath panel in place and am reluctant to remove it)

I think there are many differing mechanisms...In general I would guess a bit seizes up and needs dismantling/ lubricating.....or an "o" ring somewhere hardens,wears. If o ring..few wraps of ptfe tape gets you away.In general it is a case of having a good look and patience without taking a hammer to it!!!.With bath plug...maybe its threaded and few turns clockwise will give bit more downward pressure...Otherwise turn anti clock til it comes off and have a look..Might be just gunked up