wrench time
n.— «But the mechanics do not simply need better instruction, Mr. Joyce said. The typical mechanic, he estimates, puts in just four and a half hours of “wrench time” during an eight-hour shift. Much time is wasted traveling between subway stations.» —“$1 Billion Later, Subway Elevators Still Fail” by William Neuman New York Times May 19, 2008. (source: Double-Tongued Dictionary)
Further reading
In 1916, a small-town newspaper in Pennsylvania printed a fanciful item about a local gathering with a guest list that included, among others, Miss Ella Vader, Mr. Ray Zor, and other punny names. This is part of a complete episode. Transcript of...
A discussion on the English Language & Usage Stack Exchange about things that can still be useful even if they longer function properly, such as escalators and moving sidewalks, included several intriguing expressions involving partial failure...