LINES GP-AUXILIARY 2581588 - Caterpillar

Test (PDT)
Ensure that the maximum allowable engine rpm for the heavy lift is set to the proper value of 1250 50 rpm.Higher rpm settings can result in serious damage to the machine.
Prior to any adjustment, refer to the "Preparations" section in Testing and Adjusting, "Operational Checks".
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Left side of cab seat (1) Service connector
Install the 123-6471 Diagnostic Tool Group to the service connector (1) .Note: Refer to Special Instruction, SEHS9825 for the use of the 123-6471 Diagnostic Tool Group .
Start the engine.
Move the heavy lift switch to the ON position.
With the AEC switch in the OFF position, place the engine speed dial in the HIGH IDLE position.
Select the "Proc" mode. Use the arrow keys to select the "engine rpm" function on the PDT.
Check the engine rpm.Note: The engine rpm should be 1250 50 rpm. If the engine speed is not within the specifications, consult your Caterpillar dealer.Pressure Test (Heavy Lift ON and Heavy Lift OFF)
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The pressure tap is located in the battery compartment. (2) Load sensing signal pressure
Connect a 60000 kPa (8700 psi) pressure gauge to pressure tap (2) .
Start the engine.
Place the engine speed at the HIGH IDLE position.
Place the power mode switch in the MODE II position.
Place the heavy lift switch in the ON position.
Lower the left console.
Slowly move the bucket control lever to the full BUCKET CLOSE position. Check the load sensing signal pressure at pressure tap (2). Refer to Testing and Adjusting, "Specifications" for the correct load sensing signal pressure with heavy lift.
Place the heavy lift switch in the OFF position.
Slowly move the bucket control lever to the full BUCKET CLOSE position. Check the load sensing signal pressure at pressure tap (2). Refer to Testing and Adjusting, "Specifications" for the correct load sensing signal pressure without heavy lift.
Stop the engine.Adjustment for Load Sensing Signal Limiter Valve
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(A) Main control valve (3) Adjustment nut (4) Locknut (5) Piston (6) Spindle (7) Locknut (8) Spool (9) Signal limiter valve
Loosen the hose from signal limiter valve (9) .
Loosen locknut (4) .
Turn adjustment nut (3) clockwise until the nut contacts the stop in order to block piston (5) .Note: When adjustment nut (3) is turned in, signal pressure from the heavy lift solenoid valve is no longer required to achieve the pressure specification for heavy lift. The test should be done with the heavy lift switch in the OFF position.
Tighten nut (4) while spindle (6) is held.Adjustment for Heavy Lift Pressure
Start the engine.
Place the engine speed dial in the HIGH IDLE position.
Place the heavy lift switch in the OFF position.
Lower the left console.
Loosen locknut (7) .
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The pressure tap is located in the battery compartment. (2) Load sensing signal pressure
Slowly move the bucket control lever to the full BUCKET CLOSE position. Check the load sensing signal pressure at pressure tap (2). Refer to Testing and Adjusting, "Specifications" for the correct load sensing signal pressure with heavy lift.
To adjust the maximum pressure for the heavy lift, turn spindle (6). Turning the spindle counterclockwise will decrease the