MTS Model 512-01 Hydraulic Power Unit - Manual (Page 21)

Model 512.01 Hydraulic Power Unit Maintenance 21
Adding Hydraulic Fluid
1. The hydraulic power unit (HPU) will shut down when fluid drops
below the sight glass. Normally, it should be close to the top of the
sight glass.
Check the Fluid Level
Do not mix different brands of hydraulic fluid.
Mixing different brands of hydraulic fluid can contaminate your system.
Call MTS if you are not sure what brand of hydraulic fluid your system uses.
2. Open the filler cap. If you add fluid, add it 1 liter (1 quart) at a time.
NOTE Be sure the fluid you add is prefiltered since it may not be clean.
3. Replace the cover cap.
4. Start the HPU.
Normal Level
No Fluid Visible
CAUTION