User guide

Replacing the Return Line Filter

Model 505.07/.11 SilentFlo™ HPU Maintenance

5. Check and adjust the hydraulic fluid delivery system so that:

• Hydraulic fluid temperature stabilizes within the parameters given in

the Specifications table when the HPU is operating at high pressure.

• Pressure line reading is maintained at 21 MPa (3000 psi) maximum

static value.

• Maximum drain line back pressure is limited to 0.1 MPa (15 psi).

If you need to adjust the water-regulating valve, overtemperature switch or

pressure control valves, see the procedure for Changing the Water Flow.

Replacing the Return Line Filter

The filter element of the HPU should be replaced for the following reasons:

• When the dirty-filter indicator lights

• Whenever the hydraulic fluid is changed

• The maximum interval recommended by the filter manufacturer has passed

(1000 hours or 6 months)

Prerequisite You will need a filter element (MTS part number 100-009-495) or a filter kit

(MTS part number 100-030-195).

Procedure To change the filter element:

Note The dirty-filter indicator may light when the HPU is first started due to low

hydraulic fluid temperature. When the HPU is at normal operating

temperature, recheck the indicator to determine if the element actually

needs replacement.

1. Turn off the HPU.