pour on coal

pour on coal

old-fashioned To increase one's speed, effort, or energy. An allusion to steam-powered locomotives, which use coal furnaces to create steam. We're going to be merging onto the highway soon, so be sure to pour on coal before we reach the on ramp. What a comeback! They've certainly poured on coal since halftime, haven't they?
See also: coal, on, pour

pour on coal

increase speed. US informal
The metaphor is based on the shovelling of more coal into a locomotive's furnace.
See also: coal, on, pour