Daewoo Solar 470LC-V, Руководство по ремонту

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Page 15
Hydraulic System Troubleshooting, Testing and
Adjustment
PRESSURE UP VALVE
CHECKS AND ADJUSTMENTS
Vent hydraulic pressure from the reservoir to install an in-line "t-style" adapter and test gauge (60 bar/1,000
psi) at the pilot pump signal port relief valve outlet.
Start the engine and turn the engine speed dial to maximum. When normal operating temperature is
reached,
• Check pilot pressure and readjust it, if required;
• Select the Instrument Panel rear pump "pressure display";
• Select Power Mode;
• Stall the boom cylinder (towards the extend side);
• Read rear pump pressure on the Instrument Panel display.
Repeat all tests with and without "pressure up" selected through the console rocker switch and joystick
button.
If the two-stage main relief valve was not set correctly and main relief high-stage pressure ("pressure up")
is outside the tolerance range, begin valve adjustment by loosening the outside (widest diameter) lock nut
on the relief valve. Turn the adjusting screw clockwise to increase pressure, or counterclockwise to
decrease it. Pressure must be 350 bars (5075 psi), or up to 10 bars (145 psi) higher.
Because one adjustment can affect the other, check low-stage main relief pressure by repeating the
cylinder stall test without "pressure up." Readjust standard relief pressure by turning the inner-most
(smallest diameter) screw clockwise to increase the setting, or counterclockwise to decrease it. Pressure
should be at least 320 bars (4,641 psi), but less than 325 bars (4,714 psi).
WARNING!
This procedure should be done with two people. To reduce the chance of accident or unintended
start-up, one person should remain at the operator’s control stand while checks and
adjustments are made.
IMPORTANT
Pressure adjustments and checks cannot be made if pilot pressure is outside the specified
range. Refer to the pilot pump adjustment procedure if required, then proceed with any
necessary adjustments to main relief pressure settings.
Power Mode Operation
Main Pressure and
Tolerance
Pilot Pressure and
Tolerance
Power Mode Neutral, No Operation
20 - 40 bar
(290 - 580 psi)
30 bar + 10 bar
(435 psi + 145 psi)
Power Mode Cylinder Stall
320 bar + 5 bar
(4,641 psi + 75 psi)
30 bar + 10 bar
(435 psi + 145 psi)
Power Mode W/
Pressure Up
Cylinder Stall
350 bar + 10 bar
5,075 psi + 145 psi
30 bar + 10 bar
(435 psi + 145 psi)