SUPPORT ASSEM. 1M3955 - Caterpillar

Illustration 2 g00870228
825G Series II Soil Compactor Main Control Valve (1) Outlet port. (2) Inlet port. (3) Raise. (4) Tilt right. (6) Main relief valve. (7) Lower. (8) Tilt left. The 825G Series II Soil Compactor is equipped with a main control valve with two functions as standard equipment. The functions include a lift circuit and a tilt circuit. The left side of the soil compactor is equipped with a stabilizer bar. 826G Series II Landfill Compactor
Illustration 3 g00870231
826G Series II Landfill Compactor Main Control Valve (1) Outlet port. (2) Inlet port. (3) Raise. (6) Main relief valve. (7) Lower valve. The 826G Series II Landfill Compactor is equipped with a main control valve with a single function as standard equipment. This circuit is the lift circuit.Control Valve
Illustration 4 g00874787
Housing for the Main Control Valve (1) Outlet port. (2) Inlet port. (BB) Return oil. (CC) High pressure oil.High pressure oil from the implement pump flows into the main control valve through inlet port (2). The low pressure oil that has circulated through the main control valve will return to the hydraulic tank through outlet port (1). The housing is used on the main control valves for the 824G Series II Wheel Tractor, the 825G Series II Soil Compactor, and the 826G Series II Landfill Compactor.Hold Position
Illustration 5 g00874612
Control Valve Spool in the HOLD position (10) Work port. (11) Work port. (12) Parallel port. (13) Neutral port. (14) Spool. (15) Cavities. (16) Tank passage.Each section of the main control valve is a control valve. Each valve controls one function of the blade. The functions could be the lift, the tilt, or the tip. The control valve for the lift function operates in a similar manner to the control valve for the tip or the tilt. The lift valve is equipped with the float function.When the joystick control is in the HOLD position, the high pressure oil flows in the input port of the housing. The oil is directed to the valve section through parallel passage (12).
Illustration 6 g00874799
Control Valve Spool in the HOLD Position (12) Parallel port. (13) Neutral passage. (14) Spool. (15) Cavities. (16) Passage to the next control valve.Parallel passage (12) is ported within the valve to neutral passage (13). The high pressure oil flows around the center section of spool (14) and into cavities (15). Oil from cavities (15) will flow together. The oil flows through the passage on the opposite side of the bank valve. There will be a passage in line with neutral passage (12). This passage will be the pressure inlet to the next control valve. If the main control valve has only one bank valve the oil is diverted to tank passage (16) within the housing of the valve. The oil will flow through the outlet port to the hydraulic tank.Shifted Position
Illustration 7 g00874638
Control Valve Spool that is shifted to the Left (10) Work port. (11) Work port. (12) Parallel port. (14) Spool. (16) Tank passage. (17) Passage to the work ports. (18) Load check valve. (19)