MTS Systems SilentFlo 505G2 Series, Manual

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Maintenance
68 Series 505G2 SilentFlo™ Hydraulic Power Unit
Caution:
Mixing different brands of hydraulic fluid can contaminate your system.
Contaminated hydraulic fluid can cause premature wear of the hydraulic components in your
system.
Do not mix different brands of hydraulic fluid. MTS Systems Corporation recommends using
ExxonMobil DTE-25 or Shell Tellus 46 AW hydraulic fluid.
Procedure
See “Component Identification” to identify the components called out in the following procedure.
1. Prepare the HPU.
A. Press the Stop button to turn off the HPU.
B. Remove the electrical power to the HPU via a circuit breaker at the power source.
C. Use an 8-mm (5/16-inch) allen wrench to unlatch the HPU cover.
D. Remove the filler cap.
E. Remove the reservoir cover.
2. Remove the hydraulic fluid.
A. Use the transfer pump to remove the old hydraulic fluid from the reservoir and into an
appropriate container.
B. Open the fluid drain to remove any remaining fluid.
C. Drain the hydraulic fluid from hoses and accumulators in the system.
3. Clean the inside of the reservoir using clean cloths dampened with ethanol. Clean the pump,
motor, and bottom of the cover plate as well.
4. Use a dry cloth to wipe away the solvent.
5. Install the reservoir cover.
6. Replace the HPU filter element—see “Replacing the Return Line Filter”.
7. Add new hydraulic fluid to the reservoir.
A. Close the fluid drain.
B. Replace the filter in the transfer pump and transfer fresh hydraulic fluid (filtered to 10
microns) into the reservoir. Stop when the fluid level is full.
C. Reinstall the strainer assembly of the filter cap.
8. Run the HPU.
A. Press the Start switch.
B. Run the HPU in low pressure for three hours to clean the new hydraulic fluid.
C. Run the HPU in high pressure to check for leaks.