Zoomlion ZT20J, Service And Maintenance Manual

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6-2
6.1.3 Return oil filter
Time intervals
Run for the first time for 50 hours, and the filter element should be replaced every 300 hours thereafter.
6.2 Pressure Setting
Low temperatures can seriously affect the accuracy of pressure gauge readings. Preheat the hydraulic
system to normal operating temperature before starting the unit when testing the pressure. Recommend
to use a calibrated pressure gauge. Acceptable only if the pressure reading is within ± 5% of the
specified pressure. To ensure that all pressure settings are correct, the following operating procedures
must be strictly followed:
a. Install a pressure measuring connector on the "M" port of the main valve group and connect the
pressure gauge.
b. Start the boom lowering function, the meter reading should be 210 bar
/
3046psi.
c. The relief valve is located below the M port and rotates clockwise to increase pressure and
counterclockwise to reduce pressure.
Pressur
e tap
Overflo
w valve