Abstract: oil purifier for fuel oil or water purification processing (mixed) or points. Generally identify oil purifier fault, can pertinently maintenance, such as in overhauling confirmed when, can greatly shorten the working time, reduce Labour, but the need for management of equipment have a very clear understanding. All machinery equipment in the ship, oil purifier is a fuzzy system relative to the engineer. Due to the vague so on oil purifier is necessary for overhauling and fault : oil purifier, Overhauling, Fault diagnosis