RADIATOR & HYD OIL COOLER GP 2407098 - Caterpillar

Boom Raise Operation
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Lines group for boom cylinder (1) Supply line for boom cylinder head end (2) Boom lowering control valve (3) Supply line and return line for boom cylinder rod end
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Hydraulic Schematic of Boom Lowering Control Valve (4) Check valve (5) Port to head end of boom cylinderWhen the boom pilot control valve is moved to the BOOM RAISE position pump oil from line (1) flows into the boom lowering control valves (2). The pump oil passes through check valve (4) and flows into the head end of the boom cylinders.The oil in the rod end of the boom cylinders goes through line (3), and back to the hydraulic tank through the boom control valve.When the implement control lever is moved to the NEUTRAL position, the boom cylinders are held in the raised position. Check valve (4) prevents the oil in the head end of the boom cylinders from flowing out of the boom cylinders.Boom Lower Operation
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Lines Group (Pilot Oil and Boom Cylinders) (2) Boom lowering control valve (3) Supply line and return line for boom cylinder rod end (6) Pilot oil supply line (7) Return line for head end of boom cylinder
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Hydraulic Schematic of Boom Lowering Control Valve (8) Check valve (9) Control valveWhen the boom pilot control valve is moved to the BOOM LOWER position, pilot oil is sent through line (6) to the boom lowering control valve. The pilot oil shifts check valve (8) and control valve (9). Oil from the head end of the boom cylinders flows through the boom lowering control valves (2) and line (7) to the hydraulic tank.At the same time, main pump oil from the main control valve flows through line (3) to the rod end of the boom cylinders. Relief Operation of the Cylinder Head End
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Hydraulic Schematic of Boom Lowering Control Valve (10) Pressure relief valveWhen the boom is pushed downward by an outside force the oil pressure in the head end of the cylinder increases. The oil pressure is sensed at relief valve (10) of the boom lowering control valve. When the relief valve opens the oil flows back to the hydraulic tank. Note: The relief valve is set to open at 36300 500 kPa (5265 72.5 psi).Manual Boom Lower Operation
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(3) Supply line and return line for boom cylinder rod end. (11) Line to the bleeder valve. (13) Bleeder valve.
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(13) Bleeder valve. (14) Locknut. (15) Piston.This function is used to manually lower the boom when the engine is shut down and when no pilot oil pressure is supplied to the pilot circuit for boom lowering. The oil flows from the head end of the cylinder through line (11) to bleeder valve (13). When locknut (14) and piston (15) are slowly loosened, oil is allowed to flow through the bleeder valve. The oil flows through bleeder valve (13) to the rod end of the cylinder through line (3). The rod end of the cylinder fills with oil. The excess oil