STARTING MOTOR GP-ELECTRIC 3895796 - Caterpillar

Illustration 1 g00641012
Main Control Valve with Auxiliary Control Valve (1) Rod end line relief valve (tilt cylinder). (2) Head end line relief valve (auxiliary cylinder). (3) Head end line relief valve (tilt cylinder). (4) Rod end line relief valve (auxiliary cylinder). (5) Main relief valve for the main control valve. (6) Main relief valve with the addition of an auxiliary control valve.The line relief valve is installed in order to regulate the pressure spikes from either the implement pump or any unusual outside forces acting on the work tool. When the pressure is higher than the setting of the line relief valve, the relief valve opens. This action allows high pressure to return to the hydraulic tank. The line relief valves prevent high pressure from damaging any components in the hydraulic system.
Illustration 2 g00955449
Line Relief Valve (7) Inlet. (8) Seat. (9) Passage to the hydraulic tank. (10) Poppet. (11) Washer. (12) Spring. (13) Locking nut. (14) Adjustment screw.When the oil pressure in the circuit is less than the relief valve setting, the force of spring (12) on poppet (10) keeps poppet (10) in contact with seat (8). No oil will be allowed to flow to the hydraulic tank. Illustration 2 shows the line relief valve with the oil pressure below the adjusted pressure.
Illustration 3 g00955450
Line Relief Valve (7) Inlet. (8) Seat. (9) Passage to the hydraulic tank. (10) Poppet. (11) Washer. (12) Spring. (13) Locking nut. (14) Adjustment screw.If, there is any outside force on the work tool the oil pressure at inlet (7) will increase. If the high-pressure oil in inlet (7) exceeds the relief valve setting, the oil pressure overcomes the force of spring (12). This causes poppet (10) to move off seat (8). The oil then flows through passage (9) to the hydraulic tank. Illustration 3 shows the line relief valve with the hydraulic oil pressure higher than the adjusted pressure.Adjustment of the line relief valve is made by loosening locking nut (13). In order to raise the pressure adjustment, turn adjustment screw (14) clockwise. In order to lower the pressure adjustment, turn adjustment screw (14) counterclockwise.ReferenceFor additional information about Testing and Adjusting the line relief valves, refer to the Service Manual module for Testing and Adjusting, "Relief Valve (Line) - Test and Adjust".