A motor assembly for a paint spraying system, the motor assembly comprising: a shaft extending along an axis with a first end connected to a component of the paint spraying system; an electric motor operatively connected to the shaft to drive the shaft in a first rotational direction to power the component and increase a pressure in the component; a clutch assembly connected to a second end of the shaft opposite to the first end; a shaft adapter connecting the clutch assembly to the shaft; a pressure sensor configured to sense a fluid pressure of a pumped fluid output by the component; a controller configured to energize, based on the sensed fluid pressure, the electric motor such that the electric motor drives the shaft and to de-energize, based on the sensed fluid pressure, the electric motor such that the electric motor does not drive the shaft; and a fan connected to the clutch assembly and configured to supply the electric motor with cooling air, wherein the clutch assembly drives the fan when the electric motor drives the shaft in the first rotational direction and allows the fan to freewheel in the first rotational direction when the electric motor is not driving the shaft in the first rotational direction; wherein the clutch assembly is a roller clutch that includes roller bearings supported and retained by a body and ramps formed on the body; wherein the roller bearings are cylindrical and axially elongate; wherein the ramps are configured to engage the roller bearings to transfer torque from the electric motor to the fan and the ramps are configured to disengage from the roller bearings to allow the fan to freewheel. a shaft extending along an axis with a first end connected to a component of the paint spraying system; an electric motor operatively connected to the shaft to drive the shaft in a first rotational direction to power the component and increase a pressure in the component; a clutch assembly connected to a second end of the shaft opposite to the first end; a shaft adapter connecting the clutch assembly to the shaft; a pressure sensor configured to sense a fluid pressure of a pumped fluid output by the component; a controller configured to energize, based on the sensed fluid pressure, the electric motor such that the electric motor drives the shaft and to de-energize, based on the sensed fluid pressure, the electric motor such that the electric motor does not drive the shaft; and a fan connected to the clutch assembly and configured to supply the electric motor with cooling air, wherein the clutch assembly drives the fan when the electric motor drives the shaft in the first rotational direction and allows the fan to freewheel in the first rotational direction when the electric motor is not driving the shaft in the first rotational direction; wherein the clutch assembly is a roller clutch that includes roller bearings supported and retained by a body and ramps formed on the body; wherein the roller bearings are cylindrical and axially elongate; wherein the ramps are configured to engage the roller bearings to transfer torque from the electric motor to the fan and the ramps are configured to disengage from the roller bearings to allow the fan to freewheel.