Nabtesco GM Series - Replacing Hydraulic Oil

GM Series
TM19040 P.21/31
z Filling volume of hydraulic oil
Prepare hydraulic oil according to the amount of hydraulic oil described in the confirmation notice.
z Temperature and viscosity range of hydraulic oil
Make sure that the operating temperature range and viscosity range of the hydraulic oil do not exceed the
following ranges.
• Operating temperature range：-20～90 [℃]
• Practical viscosity range：15～500 [mm
2
/s] （Limit usage range：10～1000 [mm
2
/s]）
NOTICE
When using with a viscosity of 500 [mm
2
/ s] or more, the motor may not be able to suck oil and
may cause malfunction. In addition, if the viscosity is less than 10 [mm
2
/ s], the performance will
decrease significantly, and if it is used for a long time, the motor sliding part may get damaged,
resulting in a permanent deterioration in performance.
5.3. Replacing Hydraulic Oil
z Replacement interval
• Replace with new oil every 1000 engine hours or 1 year.
• If the deterioration of the hydraulic oil is severe even within the above replacement interval, replace it
according to the following standard.
Test items Replacement criteria
Viscosity change
（40[℃]）
[mm
2
/s] Within ±10[%]
Total oxidation [mgKOH/g]
Consult with the hydraulic oil
manufacturer because it depends on
the oil type and manufacturer.
Water content [%] Within 0.1
Impurities [mg/100mL] Within 10
Insoluble content [%] Within 0.05
Color ― Drastic change