GEAR-PINION-YM 3919872 - Caterpillar

Illustration 1 g00519586
Power train oil filter (1) Cover. (2) Bolt. (3) O-ring seal. (4) Bypass valve. (5) Washers. (6) Retainer. (7) Spring. (8) Plug. (9) Outlet tube. (10) Filter housing. (11) Seal. (12) Filter element. (13) Inlet passage. (14) Spring.Pressure oil from the oil pump goes in filter housing (10) through inlet passage (13) near the top of the housing. The oil fills the space between filter element (12) and the inside wall of housing (10). The oil normally flows through element (12) and through outlet tube (9) in the bottom of the filter housing. When the oil flows through the filter element, foreign particles in the oil are removed. The filter element prevents wear from foreign particles in the hydraulic oil.If filter element (12) is clogged with debris, oil can not pass through the filter. The oil pressure exceeds the force of the spring in bypass valve (4) and the relief valve opens. The pressure oil flows through the outlet tube in the bottom of the filter housing.
Since the oil through the oil filter bypass valve is not cleaned of foreign particles, damage can result to other components in the hydraulic system.
Make sure that the filter element is not full of debris. A clean filter element will maintain the flow of clean oil to the hydraulic system.