Flakes of metal from the engine parts are also picked up and carried in the oil. Carbon particles from incomplete combustion in the cylinders work into the oil. Some water will get into the oil, even when precautions are taken. The lubricating oil system of an engine uses strainers and filters to remove abrasives and foreign materials which tend to increase wear of engine parts and cause the lubricating oil to deteriorate. A variety of strainers and filters are used in Navy installations.
Filters remove smaller particles than strainers.
The location and number of strainers and filters will vary, depending on the type of installation. Strainers Lubricating oil strainers may be either simplex or duplex. A duplex strainer is two strainer elements in one assembly. A manual valve directs the flow of oil through either of the elements. When duplex strainers are used, one element can be bypassed, and the element can be removed and cleaned without disturbing the flow of oil through the other element to the engine.