VALVE GP-BASIC 8J7500 - Caterpillar

Machine Preparation
Clear all personnel from the machine and from the area around the machine.
Start the engine.
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Engine speed dial
Set the engine speed dial at "10".
Lower the left console.
Position the machine on level ground. Check the visibility and adjust the mirrors for the best vision close to the machine.
Fully depress the service brake pedal until the service brake pedal locks mechanically.
Increase the hydraulic oil temperature to 46° to 60° C (115° to 140° F).
Fully extend the bucket cylinder and place the bucket on the ground.
Lower the stabilizers and the blade tip.
Stop the engine.
Release the pressure in the hydraulic system.Note: Refer to Testing and Adjusting, "System Pressure - Release".
Raise the left console.
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Pilot pump pressure tap is located behind the left rear access door.
Connect tooling (B2) 34,450 kPa (5,000 psi) pressure sensors to the pilot pump pressure tap.Temporary Setting of the LS Cutoff Pressure for Medium Pressure Valve
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Medium pressure manifold
(1) Relief valve (LS cutoff) for the medium pressure function
Loosen the locknut on relief valve (1).
Turn the adjustment screw on relief valve (1) clockwise in order to increase the pressure.Note: Pressure will increase 4,000 kPa (580 psi) when the adjustment screw is moved clockwise by one turn.
While the adjustment screw on relief valve (1) is being held, tighten the locknut to the specified torque.Test Procedure
Start the engine.
Set the engine speed dial at "10".
Lower the left console.
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Power mode control button located on the soft panel switch
Push down on the power mode control button in order to activate power mode.Note: The indicator light will be illuminated when power mode is activated.
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Automatic Engine Speed Control (AESC) as displayed on the programmable function key in the monitor.
Disable the automatic engine speed control through the monitor by pressing the programmable button.
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Hydraulic modulation switch on left joystick
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Hydraulic modulation medium mode (monitor display)
Select the hydraulic modulation mode as medium. Press the lower front switch on the left joystick to select the hydraulic modulation mode.
The air conditioning should be turned off for the following test.
Stall an implement for the medium pressure circuit and hold.
Check the pressure readings at the pilot pump pressure tap. Refer to Table 1 in this manual for the correct pressure.
If the pressure is not to specification, proceed to the "Adjustment Procedure".
If the pressure is to specification, adjust line relief valve (1) on the medium pressure valve to the original setting.Note: Refer to Testing and Adjusting, "Relief Valve (Medium Pressure Function) - Test and Adjust".Adjustment Procedure
Stop the engine.
Release the pressure in the hydraulic system.Note: Refer to Testing and Adjusting, "System Pressure - Release".
Raise the left console.
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Pilot pump
(2) High-pressure cutoff adjustment screw
Loosen the locknut on adjustment screw (2) for the high-pressure cutoff valve.
Turn adjustment screw (2) on the high-pressure cutoff valve clockwise in order to increase the pressure. Turn adjustment screw (2) on the high-pressure cutoff valve counterclockwise in order to decrease the pressure.
While adjustment screw (2) on the high-pressure cutoff valve is being held, tighten the locknut to the specified torque.
Repeat the "Test Procedure" until the cutoff pressure has been