GEAR SET 0011679 - Caterpillar

Illustration 1 g01267543
(1) Bank Valve (2) End Cover (3) Implement Control Valves (4) Main Relief Valve (5) Inlet Manifold (6) Test Port (7) Inlet Port (8) Outlet PortThe implement control valves are assembled in a bank valve. Bank valve (1) is located behind an access door on the right fender of the machine. Bank valve (1) consists of inlet manifold (5), end cover (2), and either one, two, or three implement control valves (3). The four configurations of the bank valve are the following:
Bulldozer Lift
Bulldozer Lift and Bulldozer Tilt
Bulldozer Lift and Ripper Lift
Bulldozer Lift, Bulldozer Tilt, and Ripper LiftOil from the hydraulic oil pump enters inlet manifold (5) at port (7). Main relief valve (4) maintains the pressure of the hydraulic system when an implement is being operated. Refer to "Main Relief Valve" for more information on the operation of the main relief valve. The oil flows through parallel passages in the bank valve. The oil is made available to the implement control valves. The oil exits the bank valve at port (8). The oil then flows to the hydraulic oil filter.Hydraulic system pressure can be measured at port (6) .Refer to the specific section of the service manual for the control valves for more information about the operation of each valve.Main Relief Valve
Illustration 2 g01267578
(9) Chamber (10) Valve (11) Passage (12) Spring (13) Plunger (14) Chamber (15) Spring (16) Nut (17) Adjustment Screw (18) Plunger (19) Passage (20) Chamber (21) PassageThe main relief valve is a pilot operated relief valve. The main relief valve limits the pressure of the hydraulic system.Pump oil flows into chamber (9). The oil then flows through passage (21) into chamber (20). Some of the oil flows through passage (19) to plunger (18). Spring (15) keeps plunger (18) closed against plunger (13) when the pressure is low. Spring (12) and oil pressure in chamber (20) keep valve (10) closed when the pressure is low.When the oil pressure increases to the setting of the relief valve, valve (10) opens. The oil in chamber (9) flows around valve (10). The oil flows through drain passages (11) to the tank. The pump pressure can not exceed the setting of the main relief valve.The compressed length of spring (12) and spring (15) determine the force that is applied by spring (12) to valve (10). An increase or a decrease in the force that is applied by spring (12) and spring (15) changes the pressure setting of the relief valve.Loosen nut (16) and turn adjustment screw (17) clockwise in order to increase the pressure setting. Loosen nut (16) and turn setscrew (17) counterclockwise in order to decrease the pressure setting.