MTS Series 505 SilentFlo Hydraulic Power Unit Model 505-30 - Manual (Page 66)

Model 505.20 - 505.30 SilentFlo™ HPU 66
Replacing the Hydraulic Fluid
Maintenance
Replacing the Hydraulic Fluid
Replace the hydraulic fluid in the HPU reservoir whenever you have determined
that the hydraulic fluid is no longer suitable for use.
Recommended
equipment
• A transfer pump with a 10 micron filter (such as the Model 590.01 Fluid
Transfer Pump)
• Synasol or a similar cleaning solvent
• Lint-free cloths or manufactured rags
• A container for the used hydraulic oil and a small drain pan that will fit
underneath the drain plug
• A hydraulic fluid sampling kit (MTS part number 055-589-601)
• A new filter
Prerequisite
Take a sample of the hydraulic fluid to determine if it should be replaced.
Identify and correct any sources of contamination.
Mixing different types or brands of hydraulic fluid can contaminate your
system.
Contaminated hydraulic fluid can cause premature wear of the hydraulic
components (such as servovalves).
Ensure that the replacement hydraulic fluid is the same brand and type as the fluid
which is currently used the HPU reservoir. Generally, an HPU supplied by MTS
Systems Corporation will contain either Mobil DTE-25 or Shell Tellus 46AW
hydraulic fluid.
Procedure
1. Prepare the HPU.
A. Press the Stop button to turn off the HPU. If you wish, remove the
electrical power to the HPU via a circuit breaker at the power source.
B. Open the top cover of the HPU. Use a 8-mm (5/16-inch) allen wrench
to unlatch the cover.
C. Remove the filler cap.
D. 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.
CAUTION