Fuel nozzle assemblies are flushed after ultrasonic cleaning. In one embodiment, a method includes: cleaning a fuel nozzle assembly by ultrasonic cleaning; and after the ultrasonic cleaning, flushing the fuel nozzle assembly using a solution, the fuel nozzle assembly comprising a valve located in an interior of the fuel nozzle assembly, the solution flowing through the interior of the fuel nozzle assembly, and the flowing of the solution controlled by the valve.