Domestic Series 7000 Hydraulics
11
6. AUXILIARY PUMPS
6.1. The standard auxiliary pump provides pressure
for the hydrostatic power steering unit and the lift
cylinder attached to the three-point hitch.
6.2. Domestic Series 7000 tractors produced before
the 2004 season came with a single auxiliary
pump. See Figure 6.2.
6.3. Current production Domestic Series 7000 trac-
tors are fitted with a tandem auxiliary pump to
power attachments such as a back-hoe or front-
end loader. See Figure 6.3.
6.4. If performance of hydraulic features (steering or
lift cylinder) or attachments (front-end loader or
back-hoe) is poor, it is necessary to confirm that
sufficient hydraulic power is being supplied by
the pump that drives it.
Figure 6.2
Auxiliary pump
to drive steering
and lift cylinder
Hydraulic pressure
to steering unit
Figure 6.3
First auxiliary
pump
Tandem
auxiliary pump
Hydraulic pressur
to steering unit
Hydraulic
pressure to
loader valve
6.5. As with the hydrostatic drive, confirm that the
pump drive and supply are intact before drawing
conclusions about the pump itself by making
these preliminary checks:
• Check the fluid. If the fluid level is low, or the
fluid is not the correct type, both the hydrostat
and the auxiliary pump will perform poorly.
• Replace the hydraulic filter if there is any ques-
tion of its condition.
• Confirm that the suction tube that provides fluid
to the auxiliary pump from the sump of the trans-
mission is not crushed or kinked, and that the
connections are free of leaks.
• If there is no hydraulic pressure, confirm that the
pump drive is intact. The auxiliary pump is
driven by a series of gears at the front of the
transmission.
6.6. The filter and suction tubes are easily reached
for inspection with little or no disassembly.
See Figure 6.6.
Figure 6.6
Suction tube
for tandem
pump
Suction tube
for auxiliary
pump
Suction tube for
hydrostatic drive
Hydraulic
filter
To Next Page
Loading...
Need help?
General