JLG 530LRT, Руководство по обслуживанию и ремонту

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SECTION 4 - BASIC HYDRAULIC INFORMATION & SCHEMATICS
3121781 4-59
Pressure Relief Valve - Setting Procedures
Cold temperatures have a significant impact on pres-
sure readings. JLG Industries Inc. recommends operat-
ing the machine until the hydraulic system has warmed
to normal operating temperatures prior to checking
pressures. JLG Industries Inc. also recommends the use
of a calibrated gauge. Pressure readings are acceptable
if they are within ± 5% of specified pressures.
(See Main Valve Port Identification - Figure 4-15. on
page 4-54)
1. Main Relief;
a. Locate the lift up solenoid valve (SV1). It is the
middle solenoid on the main valve assembly.
b. Remove the coil nut and coil from the car-
tridge. Do not remove the wire out of the coil
plug.
c. Install a pressure gauge, 3000 PSI or higher, at
port MP1, located on the face 90 degrees
towards right.
d. Start the engine and activate lift up. The gauge
should read 2700 PSI.
e. The main relief (RV1/RV2) is located on the
same face as solenoid valve, and is the top
relief cartridge. Adjust clockwise to increase,
counter-clockwise to decrease.
f. Re-install the coil onto the lift up solenoid
valve (SV1) and torque coil nut to 5 ft. lb.s.
2. Steer Work Port Relief Valve;
a. Install a pressure gauge, 3000 PSI or higher, at
port MS, located on the top face (opposite face
to mounting hole).
b. Start the engine and activate steer right or left.
The gauge should read 2500 PSI.
c. The steer work port relief (RV2/RV3) is located
on the same face as port MP1, and is the low-
est relief valve. Adjust clockwise to increase,
counter-clockwise to decrease.
This one relief valve takes care of both right
and left.
3. Outrigger Jack Retract Relief Valve;
a. Install a pressure gauge, 3000 PSI or higher, at
port MP1 of the main control valve.
b. Start the engine and activate the auto level
function, then proceed to full extension by
using the rocker switch “trim” function.
c. Next, fully retract leveling jacks. Repeat this
cycle four more times to bleed all air from cir-
cuit.
d. The relief valve is fixed type and the relief is set
at the vendor side. The relief valve is located on
the outrigger valve, the same face as the sole-
noid valves.