Abstract: Apparatus for conditioning liquid such as lubricating oil of an engine in respect of cleaning it and regulating its temperature has, integrated into a single housing which is coupled to the engine block with aligned passages, a full flow cleaning element, a bypass centrifugal cleaning element and a heat exchanger element, the latter being formed as part of single closure element for the housing and removable for access to the cleaning elements. The heat exchange element may be disposed elsewhere in the housing and share a chamber with the full flow heating element, possibly one surrounding the other. The heat exchange element may be part of heat exchange apparatus which responds to the temperature of the liquid to effect heating or cooling to maintain a demanded temperature.

Abstract: A centrifugal fluid cleaning system includes a centrifugal cleaner through which a proportion of a circulated fluid is diverted, and a drainage assistance arrangement which includes a venturi arrangement through which non-diverted fluid is passed, the venturi developing locally a significant pressure drop in a region into which opens an induction port connected to the cleaner holding sump so that the cleaned fluid is entrained into the non-diverted fluid and returned to the circulation. While the pressure difference between inlet and induction ports is sufficient to drive the centrifugal cleaner rotor, the absolute pressures of the supply to, and drain from, the cleaner do not depend on the ambient atmospheric pressure and the overall pressure drop of the venturi arrangement is small, permitting it to be included within a closed circulation system. A pressure regulator permits bypass of the venturi arrangement to regulate the flow of fluid therethrough.