ENGINE AR-COMPLETE 2711238 - Caterpillar

Illustration 1 g02704536
Return hydraulic system (1) Main control valve (2) Return line (Swing motor) (3) Return line (Travel motors) (4) Return line (Attachment - if equipped) (5) Return passage (6) Return line (7) Bypass check valve (8) Return passage (9) Return line (10) Pilot control valve (Left joystick) (11) Return line (12) Pilot control valve (Right joystick) (13) Return line (14) Pilot supply manifold (15) Return line (16) Gear pump (17) Suction line (18) Hydraulic oil cooler (19) Return manifold (20) Return passage (21) Return oil filter (22) Hydraulic tank (23) Breather
Illustration 2 g02655437
Return hydraulic system components (1) Main control valve (2) Return line (Swing motor) (3) Return line (Travel motors) (4) Return line (Attachment - if equipped) (6) Return line (7) Bypass check valve (8) Return passage (9) Return line (10) Pilot control valve (Left joystick) (11) Return line (12) Pilot control valve (Right joystick) (13) Return line (14) Pilot supply manifold (15) Return line (17) Suction line (18) Hydraulic oil cooler (19) Return manifold (21) Return oil filter (22) Hydraulic tank (23) BreatherThe return hydraulic system routes oil that is used for machine operation back to hydraulic tank (22). Return oil filter (21) is located inside hydraulic tank (22) and is used to filter the hydraulic oil. Hydraulic oil cooler (18) maintains the hydraulic oil at the optimum temperature.The return oil flow from main control valve (1) flows to passage (5). The oil then flows to return line (6). The return oil flow takes one of two paths to return manifold (19) :
When the hydraulic oil is cool, most of the return oil flows through bypass check valve (7) to passage (8) .
When the hydraulic oil is warm, most of the return oil flows through line (9) to hydraulic oil cooler (18) .The return hydraulic oil from passage (8) and hydraulic oil cooler (18) flows into return manifold (19) .The return oil from return line (2), return line (3) and return line (4) flows directly to return manifold (19) .The combined return oil flow in return manifold (19) then flows through passage (20) into return oil filter (21). The filtered return oil then flows into hydraulic tank (22) .Note: If there is an obstruction in the filter element, the oil will bypass the filter element of return oil filter (21) .Return oil flow from pilot control valve (10) flows through line (11) directly to hydraulic tank (22). Return oil flow from pilot control valve (12) flows through line (13) directly to hydraulic tank (22). Return oil flow from pilot supply manifold (14) flows through line (15) directly to hydraulic tank (22) .Gear pump (16) receives oil from hydraulic tank (22). The hydraulic oil flows through suction line (17) to gear pump (16). Breather (23) prevents a pressure or vacuum condition in hydraulic tank (22).