HOUSING ASSEM. 7N4171 - Caterpillar

Illustration 1 g03666249
Oil filter components (1) Inlet passage from pump (2) Outlet passage (3) S O S port (4) Switch (5) Pressure (6) Bypass valvePressure oil from the pump goes into the housing assembly through inlet passage (1) . The oil flows into the space between the inside of the filter housing and the filter element.During normal operation, the oil flows through the filter element and out through passage (2) . The filter element stops most debris that is in the oil.If the filter element becomes full of debris, the restriction to the flow of oil causes a pressure increase. The increase in pressure will force bypass valve (6) to open. The oil bypasses the filter and flows directly to outlet passage (2) .
When the oil does not go through the filter element, the debris in the oil damages other components in the hydraulic system.
Correct maintenance must be used in order to make sure that the filter element does not become full of debris. A filter element that is clogged with debris will stop the flow of clean oil to the hydraulic system.