LINER 1793167 - Caterpillar

Do not exceed the air pressure of 830 35 kPa (120 5 psi) or damage can occur to the air system components.
Connect the steering system to 1U-5000 Auxiliary Power Supply. Refer to Special Instruction, SEHS8715 and Special Instruction, SEHS8880.
Personal injury or death could result when towing a disabled machine incorrectly.Block the machine to prevent movement before releasing the brakes. The machine can roll free if it is not blocked.
Reference: See Operation And Maintenance Manual, "Towing The Machine" for more towing information.Reference: See Testing And Adjusting, "Towing The Machine - Preparation" for the towing procedure.Ensure that the parking brake lever is in the ON position. Push in the knob of the parking brake reset valve.Place the parking brake lever in the cab to the OFF position. Air will enter the parking and secondary brake valve which will cause the control spool to move. This will prevent oil from returning to the hydraulic tank when the electric drive pump for the parking and the secondary brake release is operating. The electric drive pump for the parking and the secondary brake release will be used to supply oil in order to release the parking and secondary brakes. The electric drive pump for the parking and the secondary brake release is operated by a switch that is located in the cab. The hydraulic oil will flow from the pump through the parking and secondary brake valve to the brakes. The oil will be used to release the spring applied parking brakes.
Illustration 1 g00530747
Towing schematic
(1) Pilot oil for the hoist control valve
(2) Relief valve
(3) Air flow to the parking and secondary brake valve
(4) Oil flow to the rear brake cooling circuit
(5) Oil flow to the front brake cooling circuit
(6) Return oil flow back to tank
(7) Oil chamber for the parking brakes (all four brakes)
(8) Rear brake cooling pump section
(9) Suction screen
(10) Hydraulic tank
(11) Check valve that is inside the pump
(12) Electric powered parking and secondary brake release pump
(13) Electric motor
(14) Electrical leads to the switch in the cab
(15) Parking brake release hydraulic filter
(16) Parking brake release pump section
(17) Check valve
(18) Parking and secondary brake valve
(19) Relief valve that is inside the pump Note: Arrows show oil flow.
Illustration 2 g00280797
Electric drive pump for the parking and the secondary brake release
(12) Electric drive pump for the parking and the secondary brake release
(13) Electric motor
Illustration 3 g00875343
Location of the parking brake lever and the parking brake reset valve
(20) Parking brake reset valve
(21) Parking brake lever
Illustration 4 g00672723
Location of the switch for the electric drive pump for the parking and the secondary brake release