HUB-PILOT 2518311 - Caterpillar

Illustration 1 g01432192
(4) Adjustment screw
(5) Locknut
(6) Adjustment plug
(7) Locknut
(8) Main relief valveNote: Adjustment screw (4) of main relief valve (8) must always be set to the maximum clockwise position. All pressure adjustments of the main relief valve must be made with adjustment screw (6). Do not loosen locknut (5) or turn adjustment screw (4) of the main relief valve in order to adjust the main relief valve pressure setting.
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".
Illustration 2 g01428847
Pump compartment
(1) Pressure tap (delivery pressure for drive pump)
(2) Pressure tap (delivery pressure for idler pump)
(3) Pressure tap (power shift pressure)
Attach a 60000 kpa (8700 psi) pressure gauge to pressure tap (1).
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 engine rpm settings.
Increase the hydraulic oil temperature to 55° 5°C (131° 9°F).
Slowly move the joystick for the stick to the STICK OUT position (full retraction of the stick cylinder). Check the pressure gauge reading at pressure tap (2). The pressure setting should be 35000 +500 - 2000 kpa (5076 +72 -290 psi).
Return the joystick for the stick to the NEUTRAL position.
If the main relief valve pressure setting is not within the specification, adjust the main relief valve pressure setting.
Illustration 3 g01434292
Top of main control valve
(6) Adjustment screw
(7) Locknut
(8) Main relief valve
In order to adjust the main relief valve, loosen locknut (7) and turn adjustment screw (6) until the pressure gauge reading at pressure tap (2) is 35000 +500 - 2000 kpa (5076 +72 -290 psi).Note: Turning adjustment screw (4) clockwise increases the pressure. Turning adjustment screw (4) counterclockwise decreases the pressure.Note: Always make final pressure adjustments on pressure rise.
Tighten locknut (5) to a torque of 50 10 N m (37 7 lb ft).Temporary Setting of the Main Relief Valve
Note: A temporary setting of the main relief valve is required before any line relief valve can be adjusted.
The main relief valve pressure setting should be 35000 +500 -2000 kpa (5076 +72 -290 psi). If the main relief valve is not within the specification, adjust the main relief valve pressure setting to the correct pressure specification before performing Step 2. Refer to Testing and Adjusting, "Relief Valve (Main) - Test and Adjust".
Illustration 4 g01434292
Top of main control valve
(6) Adjustment screw
(7) Locknut
(8) Main relief valve
Loosen locknut (7) and turn adjustment screw (6) clockwise for one quarter turn. Tighten locknut (5) to the specified torque.Note: Always make final pressure adjustments on pressure rise.