Hyundai r35z-7 Workshop Manual page 40

( ( 3) Changing the hydraulic oil
After 2000 hours of operation.
Every 2000 hours of operation or once a year after that.
The change interval may have to be shortened depending on the degree of fouling and the
thermal load condition of the hydraulic oil.
If the hydraulic oil is not appropriate and need be changed, pay attention to the following points :
Be sure to control the oil temperature below the highest temperature and above the lowest
temperature during operation in winter and summer.
Pay attention to the following points during change of the hydraulic oil :
- Change the hydraulic oil as a whole quantity.
- Do not allow dust to mix into the circuit.
- Clean the tank inside.
- Supply the oil through the filter.
(4) Checking for the oil leakage
Daily during the initial period after startup.
Once a week when the operation becomes stable.
(5) Checking the temperature
Monitor the temperature continuously.
When the viscosity is above the allowable value because of low hydraulic oil temperature,
warm-up operation is necessary.
Start the motor with the speed set to about one half of the rated speed, then operate the actuator
under the load for a short period.
When the oil temperature is below the allowable ambient temperature, it is necessary to preheat
the oil tank before start of the motor.
Take care not to allow the hydraulic oil temperature to exceed +90
2-8
C