FILM-INSTRUCTION 1255753 - Caterpillar

Machine Preparation
Note: A temporary setting of the main relief valve pressure is required before any line relief valve pressure setting is adjusted. Refer to the temporary setting of the main relief valve pressure in Testing and Adjusting, "Relief Valve (line) - Test and Adjust" for the machine.
Position the machine on level ground and stop the engine.
Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "Hydraulic System Pressure - Release" for the machine.
Illustration 1 g03707147
Pump Compartment
(1) Pressure tap (drive pump)
(2) Pressure tap (idler pump)
(3) Pressure tab (power shift)
Install a pressure gauge with a 60000 kPa (8700 psi) capacity on pressure tap (1) for the drive pump.
Start the engine.
Place the machine controls at the following settings: engine speed dial 10 and AEC switch OFF. Refer to Testing and Adjusting, "Engine Performance - Test (Engine Speed)" for the machine for engine rpm settings.
Warm the hydraulic oil to 50 °C (122 °F).
Set the pilot pressure to the specifications in Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust" for the machine.
Set the main relief valve to specifications. Refer to Testing and Adjusting, "Relief Valve (Main) - Test and Adjust" for the machine.
Calibrate the power shift pressure. Refer to Testing and Adjusting, "Calibration" for the Machine Electronic Control System.
Illustration 2 g03707149
Line relief valve (typical example)
(4) Locknut
(5) Adjustment screw
Illustration 3 g03707151
(6) Upper line relief valve
(7) Lower line relief valve Note: To prevent oil flow to the work tool during this testing and adjusting procedure, close the stop valves in the lines for the work tool.Adjustment of the Line Relief Valve for Attachment Control Valve
Table 1
Pressure Settings for the Line Relief Valve
312D2 and 313D2 32000 500 kPa (4641 72.5 psi)
318D2 37000 500 kPa (5367 72.5 psi)
Select a work tool that provides two-way flow. Refer to Testing and Adjusting, "Work Tool - Select" for the Tool Control System.
To adjust the pressure setting of the upper line relief valve (6) for the work tool, press