Procedure
W
Warning
This service procedure may require disabling the vehicle / machine (raising the wheels off the ground,
disconnecting work function) while performing, to prevent injury to the technician and bystanders. Take
the necessary safety precautions.
Always follow this procedure when starting-up a new H1 installation or when the motor has been
removed.
1. Before installing the motor, inspect the units for possible damage incurred during shipping and
handling.
2. Make certain all system components (reservoir, hoses, valves, fittings, heat exchanger, and so forth)
are clean before filling with fluid.
3. Fill the reservoir with recommended hydraulic fluid. Pass this fluid through a 10 micron (nominal, no
bypass) filter before it enters the reservoir.
4. Fill the inlet line leading from the reservoir to the pump.
5. Check inlet line for properly tightened fittings. Make sure the inlet line is free of restrictions and air
leaks.
6. Fill the motor and pump housings with clean hydraulic fluid before start up. Fill by pouring filtered oil
into the upper case drain port.
C
Caution
Never start the prime mover unless the motor and pump housings are filled completely with clean
hydraulic fluid.
7. For closed loop systems, install a 0-60 bar [0-1000 psi] pressure gauge in the charge pressure gauge
port of the pump to monitor the charge pressure during start-up.
For open circuit systems, use gauges in system ports.
8. Disconnect any external control input signal from the pump control until after initial start-up. This
ensures that the pump remains in its neutral position.
9. Jog (slowly rotate) prime mover until charge pressure starts to rise.
10. Start the prime mover and run at the lowest possible speed until charge pressure builds.
W
Warning
Do not start the prime mover unless the pump is in neutral position (swash plate at 0° angle). Take
necessary precautions to prevent machine movement in case pump is actuated (in stroke) during
initial start-up.
If necessary, bleed excess air from the high pressure lines through the high pressure system gauge
ports.
11. Once charge pressure is established, increase to normal operating speed. Charge pressure should be
as indicated in the pump model code. If charge pressure is low, shut down and determine cause.
C
Caution
Low charge pressure may affect ability to control the machine.
12. Shut down the prime mover.
13. Connect the external control input signal.
14. Reconnect the machine function if disconnected earlier.
15. Start the prime mover, checking to ensure the pump remains in neutral.
Service Manual
H1F Bent Axis Fixed Displacement Motors, Size 080
Initial startup procedures
©
Danfoss | December 2023
AX465363259664en-000102 | 21
