Quick thinking from engineers prevented cement from setting in the Victoria Line signal room which would have caused even further disruption to commuters.
Peter McNaught, operations director for the Bakerloo, Central and Victoria lines, said it was lucky workers knew sugar would stop the cement setting.
Normal service has resumed on the line after engineers worked throughout the night to repair the damage.
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But while he wasn't showing it, PC Tyler O'Hare was enjoying every minute of it.
The suffragist leader has been immortalised in bronze in Parliament Square.
Commuters could be caught out by the alterations which will see many existing trains leaving stations up to two minutes early.