MOTOR AS 7T2054 - Caterpillar

Illustration 2 g06217670
Stop valves for high-pressure oil delivery to the work tool (typical example)
Close the stop valves that are mounted on each side of the stick in order to prevent oil flow to the work tool during this procedure.
Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "System Pressure - Release"
for the machine.
Illustration 3 g06180512
Pump compartment (typical example)
(1) Pressure tap (delivery pressure for pump 1)
(2) Pressure tap (delivery pressure for pump 2)
Attach both 41,368 kPa (6,000 psi) pressure sensors to pressure tap (1) and pressure tap (2).Test Procedure
Note: A temporary setting of the main relief valve is required before any line relief valves can be adjusted. Refer to Table 3 for temporary main relief setting for the function being tested.
Table 3
Attachment Valve Position Temporary Main Relief Setting
Extend 37000 500 kPa (5366 73 psi)
Retract
Table 4
Relief Valve Pressure Change With One Turn Of Adjustment Screw
Main relief valve 14400 kPa (2100 psi)
Line relief valves 19800 kPa (2871 psi) Note: Pressure values in Table 4 are approximate values. Use a pressure gauge for adjustment.
Start the engine.
Select a work tool to meet the following conditions.
Two-way flow from one pump
Variable relief valve pressure set at the default specifications of 40,000 kPa.Refer to Testing and Adjusting, "Work Tool - Select" for the Tool Control System.
Place the hydraulic activation control lever in the UNLOCKED position.
Place the machine controls at the following settings: engine speed dial "7" and AEC switch OFF. Refer to Testing and Adjusting, "Engine Performance - Test (Engine Speed)" for engine rpm settings.
Increase the hydraulic oil temperature to 55° 5°C (131° 9°F).
Move the joystick for the stick until the stick is at the full STICK OUT position (full retraction of the stick cylinder).
Check the main relief valve pressure setting at pressure tap (1) or pressure tap (2). The main relief valve pressure setting should be 35000 500 kPa (5076 73 psi).
Illustration 4 g06195051
Main relief valve (standard)
(A) Adjustment screw
(L) Locknut
Illustration 5 g06195116
Main relief valve (heavy lift)
(A) Adjustment screw
(L) Locknut
Loosen the locknut. Set the main relief pressure to 37000 500 kPa (5366 73 psi). Tighten the locknut.Note: Turn the adjustment screw clockwise in order to increase the pressure. Turn the adjustment screw counterclockwise in order to decrease the pressure.Note: Always make final pressure adjustments on pressure rise.
Verify the temporary main relief pressure setting with a second function. Move the joystick for the boom until the boom is at full BOOM RAISE position (full extension of the boom cylinder). The main relief pressure should be 37000 500 kPa (5366 73 psi).
Illustration 6 g06263325
Line relief valves for the attachment control valves (typical example)
(3) Main relief valve
(4) Line relief for attachment 1 control valve (extension)
(5) Line relief for attachment 1 control valve (retraction)
(6) Line relief for attachment 2 control valve (extension)
(7) Line relief for attachment 2 control valve (retraction)
Follow Step 11 to Step 17 for each line relief valve, refer to illustration 6 for the relief valve locations.
Mark the original position of the line relief for the attachment