set (one's) shoulder to the wheel
To make a sustained, concentrated, and vigorous effort; to work very hard and diligently. After I was nearly expelled in my first year of college, I decided to stop fooling around, set my shoulder to the wheel, and get as much out of my degree as I could. I know that the new deadline is tight, but if everyone sets their shoulders to the wheel, I know we can get it done in time!