Standard procedures, removing the pump
Before working on the pump, thoroughly clean the outside. If the pump has an auxiliary pump attached,
remove both pumps as a single unit. Tag and cap all hydraulic lines as you disconnect them, and plug all
open ports to ensure that dirt and contamination do not get into the system.
C
Caution
Contamination can damage internal components and void the manufacturer's warranty. Take
precautions to ensure system cleanliness when removing and installing system lines.
Removal
1. With the prime mover off, thoroughly clean all dirt and grime from the outside of the pump.
2. Tag, disconnect, and cap each hydraulic line connected to the pump. As hydraulic lines are
disconnected, plug each open port, to ensure that dirt and contamination do not get into the pump.
3. Remove the pump and its auxiliary pump (if applicable) as a single unit.
Be careful, do not damage solenoids and electrical connections when using straps or chains to
support the pump.
Inspection
1. Ensure the work surface and surrounding area are clean and free of contaminants such as dirt and
grime.
2. Inspect the system for contamination.
3. Look at the hydraulic fluid for signs of system contamination, oil discoloration, foam in the oil, sludge,
or metal particles.
Replacement
1. Before replacing the pump, replace all filters and drain the hydraulic system. Flush the system lines
and fill the reservoir with the correct, filtered hydraulic fluid.
2. Fill the pump with clean, filtered hydraulic fluid.
3. Attach the pump to the prime mover. Torque mounting screws according to the manufacturers
recommendation.
4. Replace all hydraulic lines. Ensure the charge inlet line is filled with fluid.
Electric control module
Removal
Refer to the exploded diagram.
1. Using a 5 mm internal hex wrench, remove the six cap screws (D250).
2. Remove the control module and gasket (D150). Discard the gasket.
3. If necessary, remove orifices (F100) using a 3 mm internal hex wrench. Tag and number them for
reinstallation.
Inspection
Inspect the machined surfaces on the control and top of the pump. If you find any nicks or scratches,
replace the component.
Reassembly
Ensure you install dowel pins (D300) in housing before installing control.
Service Manual
H1 45/53/60/68 Tandem Closed Circuit Axial Piston Pumps
Minor repair
©
Danfoss | June 2018
520L0928 | AX00000103en-US0303 | 47
