Cub Cadet Domestic Series 7000 Service Manual page 17

6.16. Disconnect the output line from the top of the
pump using a 3/4" wrench and a 9/16" wrench.
6.17. Install the gauge set in-line between the auxiliary
pump and the steering pump. The pressure
gauge should be near the auxiliary pump, and
the flow meter should be near the steering unit.
6.18. Set the parking brake, place the gear selector in
neutral, open the flow valve on the gauge set all
the way, and confirm that no unsafe conditions
will be created by starting the tractor engine.
See Figure 6.18.
Flow
meter
Figure 6.18
6.19. Start the engine, allow the engine and hydraulics
to warm-up.
6.20. Performance:
• The SKP1/4.3 S auxiliary pump does not contain
a relief valve. It is capable of producing roughly
3600 PSI (250 bars) at engine speeds beyond
1,200 RPM.
• This is far in excess of the needs of the rest of
the system, which is designed to operate at
1,500 PSI (103 Bars).
• For our purposes, it is not necessary to test the
pump to its full capacity, only to establish that it
produces enough flow and pressure to operate
the hydrostatic steering and hydraulic lift cylin-
der.
• The auxiliary pump was observed to move about
4.6 Gal./min. (15 L/min.) at an engine speed of
3,000 RPM, with no load applied.
• Flow will vary with engine speed, but pressure
tests can be done at lower engine speeds:
1,200-1,500 RPM.
Pressure
guage
Flow
valve
Domestic Series 7000 Hydraulics
• Set the throttle to maintain an engine speed in
this range, and note the reading on the flow
meter.
6.21. Close the flow valve until the pressure gauge
reads 1,500 PSI (103 Bar). Note the flow read-
ing. See Figure 6.21.
6.22. As soon as the flow reading is noted, open the
the flow valve completely, relieving pressure
from the system. Turn -off the engine.
6.23. The flow readings noted at zero pressure and
1,500 PSI (103 Bars) should not vary signifi-
cantly. Flow is more related to engine RPM than
to pressure.
13
Figure 6.21