Bolt Circles, 2-Bolt B Flange, 182-184 TC, 213-215 TC, 254-256 TC The bracket is mounted to both the pump and the engine or motor. A mounting bracket is used to keep the motor or engine and the pump attached to one another. The jaw coupler connects the shafts together, while the center spider fills the gap between the shafts. Electric Motor Bracket: 5 3/4 in.