SEAL GP-DUO-CONE 2069211 - Caterpillar

Illustration 1 g00530166
(1) Hoist proportioning solenoid for SNUB, FLOAT, and LOWER
(2) High pressure relief valve
(3) Low pressure relief valve
(4) Hoist proportioning solenoid for RAISE
(5) Rear brake oil cooler relief valve
(6) Outlet to the hoist and brake hydraulic tank
(7) Outlet to the head end of the hoist cylinders
(8) Outlet to the rod end of the hoist cylinders
(9) Outlet to the rear brake oil cooling system
(10) Inlet for pump oil
Illustration 2 g00530168
(1) Hoist proportioning solenoid for SNUB, FLOAT, and LOWER
(2) High pressure relief valve
(3) Low pressure relief valve
(4) Hoist proportioning solenoid for RAISE
(5) Rear brake oil cooler relief valve
(6) Outlet to the hoist and brake hydraulic tank
(7) Outlet to the head end of the hoist cylinders
(8) Outlet to the rod end of the hoist cylinders
(9) Outlet to the rear brake oil cooling system
(10) Inlet for pump oil
(11) Hoist and brake hydraulic tank
(12) Brake pump section
(13) Hoist pump section
(14) Parking brake release hydraulic filter
(15) Hoist and brake gear pump
(16) Line to the parking and secondary brake valve
(17) Check valve
(18) Pilot oil line from the parking brake release system
(19) Hoist control valve
(20) Stem
(21) Dump spool
(22) Directional spool
(23) Actuators
(24) Centering springs
(25) Hoist cylinders
(26) Orifices Oil flows from the brake pump section (12) of the hoist and brake gear pump. This oil flows through parking brake release hydraulic filter (14). This oil will go through check valve (17). The oil flow is then split. Most of the oil is sent to the parking and secondary brake valve through line (16). The rest of the oil goes to hoist control valve (19) through line (18). This oil is used as pilot oil for hoist proportioning solenoid (1) and hoist proportioning solenoid (4). Pilot oil is always present at both ends of directional spool (22). The hoist proportioning solenoids are used to drain the pilot oil from the ends of directional spool (22), which then allows the spool to move.Oil flows through hoist pump section (13) of hoist and brake gear pump (15). This oil flows through line (10) to hoist control valve (19). The hoist control valve will send pump oil to one of two locations. When the dump body is being raised or lowered, the hoist cylinders receive the oil. If the hoist is not being used, the oil flows to the oil cooling system for the rear brakes.Rear brake oil cooler relief valve (5) limits the pressure in line (9) to the rear brake oil cooler. Rear brake oil cooler relief valve (5) will vent oil to hoist and brake hydraulic tank (11), when the pressure in line (9) is too high.Low pressure relief valve (3) limits the pressure in line (8) to the rod end of hoist cylinders (25) when the dump body is being lowered. Low pressure relief valve (3) will open when the pressure in line (8) becomes too high. When low pressure relief valve (3) opens, dump spool (21) will open and oil will vent to hoist and brake hydraulic tank (11).When the dump body is being raised oil is sent