SEAL 0826422 - Caterpillar

Table 1
Description Specification
MH3059 MH3049
Line Relief Valve (Swing Right) "Port Relief A" 41368 kPa (6000 psi) to 41023 kPa (5950 psi) 38128 kPa (5530 psi) to 37783 kPa (5480 psi)
Line Relief Valve (Swing Left) "Port Relief B" 41368 kPa (6000 psi) to 41023 kPa (5950 psi) 38128 kPa (5530 psi) to 37783 kPa (5480 psi)
High-Pressure cut off valve "POR" 37920 kPa (5500psi) to 37576 kPa (5450 psi) 35163 kPa (5100 psi) to 34818 kPa (5050 psi) Rework Procedure
Use the following procedure to set new pressure setting:Machine Preparation
Clear all personnel from the machine and from the area around the machine.
Start the engine.
Place the hydraulic activation control lever in the UNLOCKED position.
Press Button "A" on the monitor to set the engine speed at "Max Speed".
Push down on the parking brake control button to de-activate the parking brake.
Increase the hydraulic oil temperature to above 49° C (120° F).
Position the machine on level ground. Check the visibility and adjust the mirrors from the best vision close to the machine.
Push down on the stabilizer control button to lower the stabilizer to the ground.
Push down on the parking brake control button to activate the parking brake.Test Procedure
Illustration 1 g06106394
Swing Pump
(1) Actuator Piston (Mechanical Zero)
(2) Swing Brake Adjustment
(3) Regulator Valve (Throttle Spool Piston)
(4) Swing Left Pump Line Relief Valve
(5) Charge Pressure Valve
(6) Pressure Cut off Valve
(7) Supply Oil to Swing Motor for Left Swing
(8) Swing Right Pump Line Relief Valve
Illustration 2 g06106397
Swing Pump
(9) Supply Oil to Swing Motor for Right Swing
(10) Swing Pump Purge
(11) Swing Pump Line Relief Pressure Sensor
(12) High-Pressure Cut off Valve
(13) Case Drain (to Swing Motor)
Illustration 3 g06106399
Pressure taps are located behind the left rear access door.
(14) Swing circuit pressure (Port A)
(15) Swing circuit pressure (Port B)
Set Engine Speed to 1500 RPM.
Attach pressure gauges on Swing circuit pressure (Port A) (14) and Swing circuit pressure (Port B) (15) ports.
Engage Swing Brake.
Extend Boom and Swing against an immovable object (machine should not move). Read high side pressure at A or B. Record this reading as the "High-pressure cutoff valve" setting.
Turn "High-pressure cutoff valve" (12) set screw full clockwise to max setting then back off 1/8th of a turn. Refer Illustration 2.
Extend Boom and Swing Right against an immovable object (machine should not move). Read high side pressure at A or B. Record this reading as the "Line Relief valve (swing right)" setting.
Extend Boom and Swing Left against an immovable object (machine should not move). Read high side pressure at A or B. Record this reading as the "Line Relief valve (swing left)" setting.Adjust Procedure
Set engine speed at 1500 RPM (hydraulic system temperature should still be > 49° C (120°)).
Swing Left and Swing Right Line Relief Valve Adjustment (4) and (8) "Port Relief A" and "Port Relief B"
Override machine sensors.
Make sure that Swing Brake is applied.
Swing Left (machine should not move).
Loosen the locknut on the line relief valve for the swing circuit that was tested.
Turn the adjustment screw until the pressure reading at the swing circuit pressure tap has reached the correct