PURPOSE: To dispense with the fixing of a product on an essential precision tolerance zone during a cleaning operation by comprising a means for communicating a first end of a passage to the cleaning fluid, and a cleaning fluid conduit means communicated to a second end of the passage.

CONSTITUTION: A cleaning apparatus comprises a cleaning fluid CF container 10, and a means for communicating the first ends 30a, 32a of the internal passages 30, 32 for articles such as a fuel passages and the like, to the cleaning fluid CF. Further it comprises a cleaning fluid conduit means communicated to the second ends 30b, 32b of the passages 30, 32, and the fluid CF is drawn from the container 10 in accordance with the flow of the cleaning fluid CF passing through this conduit means, so that the fluid CF flows to the second ends 30b, 32b from the first ends 30a, 32a through the passages 30, 32. Further a valve means is installed for directing the cleaning fluid CF in the conduit means into the container 10 by flowing the fluid CF in the direction of the first ends 30a, 32a from the second ends 30b, 32b through the passages 30, 32.