TUBE AS 6W6724 - Caterpillar

Pressure Reducing Valve for the Hook Winch Brake
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Pressure tap for the pressure reducing valve for the hook winch brake
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6V-7830 Tetragauge
Attach a 6V-7830 Tetragauge to the pressure tap that is shown and start the engine. Set the throttle to the HIGH IDLE position.
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Hook winch controls (1) QUICK DROP (2) LOWER (3) HOLD (4) RAISE
Move the hook control lever to LOWER position (2). The high reading on the gauge is the setting for the brake release pressure.
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Combination valve (5) Pressure reducing valve
The pressure from step 2 should be 5500 170 kPa (800 25 psi). If the pressure is not correct, adjust pressure reducing valve (5) to the proper pressure. Turn the adjustment screw clockwise in order to increase the pressure. Turn the adjustment screw counterclockwise in order to decrease the pressure.Counterbalance Valve for the Hook Winch
High hydraulic system pressure. To avoid personal injury, do not remove any hydraulic system lines, taps, or parts until all pressure has been relieved.
Refer to Testing and Adjusting, "Machine Preparation" before performing the following procedure.
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Location of the counterbalance valveThe counterbalance valve is used to control the hook winch motor when the hook is powered down. The counterbalance valve is attached to the combination valve.
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Location of the pilot line for the counterbalance valve
Remove the pilot line from the fitting on the LOWER port of the hook winch motor. Install a 6V-9829 Cap Assembly on the fitting. Leave the pilot line open to the atmosphere during the test.Note: A small amount of oil will leak from the pilot line during the test. Use a small container to catch the oil leakage.
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Hook winch motor (1) Test port
Remove the plug from test port (1) in the hook winch motor.
Install a 8T-3613 Valved Nipple Assembly in test port (1) .
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Attach a 6V-7830 Tetragauge to the pressure tap.
Start the engine and set the throttle to the LOW IDLE position.
Move the hook control lever to the LOWER position. The high reading on the gauge is the approximate setting of the counterbalance valve.Note: The factory setting of this valve is 18600 kPa (2700 psi). The reading on the gauge may be higher. This is due to the flow rate of the hydraulic oil through the valve.
The gauge should read 18600 + 3450 - 0 kPa (2700 + 500 - 0 psi). If the pressure is not correct, adjust the counterbalance valve to the proper pressure. Turn the adjustment screw counterclockwise in order to increase the pressure setting. Turn the screw clockwise in order to decrease the pressure setting.