Clean your clock

Does anyone know the origination/true translations of the phrase:
"clean your clock"

'Clock' was certainly Cockney slang for 'face' when I was a boy. This may help give an explanation. More I don't know.

To clean someone's clock (for them) means to punch someone in the face. Clock is indeed London slang for face, though it is not as far as I know rhyming slang - and is simply derived from clocks also having faces. Why "to clean" should in this case mean to hit or strike is beyond me.

To access previous discussions about "clean your clock," type in "clock" under the archive search. I don't think anyone came up with a definitive answer. My interpretation of the meaning: to best someone in a confrontation, physical or otherwise.

Just for reference, the more usual Cockney slang term for "face" is "boat". This is rhyming slang, and a contraction of "boat race". Why "boat race"? I suppose because there is a famous boat race held every year along the river Thames between the universities of Oxford and Cambridge, and so this phrase would be somewhat relevant to any inhabitant of London.