Toro Groundsmaster 4000-D Service Manual page 89

Procedure for Steering and Lift/Lower Gear Pump
Flow Test
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine for approximately 10
minutes. Make sure the hydraulic tank is full.
2. Park machine on a level surface with the cutting
decks lowered and off. Make sure engine is off and the
parking brake is applied.
CAUTION
Prevent personal injury and/or damage to equip-
ment. Read all WARNINGS, CAUTIONS and Pre-
cautions for Hydraulic Testing at the beginning
of this section.
IMPORTANT: Make sure that the oil flow indicator
arrow on the flow gauge is showing that the oil will
flow from the pump section, through the tester and
into the hydraulic hose.
3. With the engine off and cutting decks lowered, dis-
connect the hydraulic hose from the 90
third gear pump section which supplies the steering and
lift/lower circuits (Fig. 43).
4. Install tester in series between the fitting and the dis-
connected hose. Make sure the tester flow control valve
is OPEN.
IMPORTANT: The pump is a positive displacement
type. If pump flow is completely restricted or
stopped, damage to the pump, tester or other com-
ponents could occur.
5. Start the engine and move throttle to full speed (2870
RPM). DO NOT engage the cutting decks.
6. While watching pressure gauges, slowly close flow
control valve until 1000 PSI (69 bar) is obtained on
gauge. Verify engine speed continues to be 2870 RPM.
GAUGE READING TO BE: Flow approximately 7
GPM (26.3 LPM) at 1000 PSI (69 bar).
7. Stop engine and record test results.
8. If a pressure of 1000 PSI (69 bar) could not be ob-
tained or flow is lower than 6 GPM (22.3 LPM) (85% of
expected flow), check for restriction in pump intake line.
If intake line is not restricted, consider that gear pump is
worn or damaged.
9. When testing is complete, remove tester and recon-
nect hose to pump fitting.
Groundsmaster 4000--D
2
4
1. Gear pump
2. Fan drive manifold
o
fitting in the
Page 4 - - 55
3
1
Figure 43
3. Steering/lift hose
o
4. 90 fitting
Hydraulic System