Toro Groundsmaster 4000-D Service Manual page 85

Procedure for Steering Circuit Relief Pressure 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.
3. Connect a 5000 PSI (350 bar) pressure gauge onto
steering pressure test port.
4. Start the engine and move throttle to full engine
speed (2870 RPM).
IMPORTANT: Hold steering wheel at full lock only
long enough to get a system pressure reading.
Holding the steering wheel against the stop for an
extended period can damage the steering valve.
5. Turn steering all the way in one direction and mo-
mentarily hold the steering wheel against resistance.
GAUGE READING TO BE 1300 to 1400 PSI (90 to
96 bar).
6. Stop the engine and record test results.
7. If pressure is incorrect, inspect steering relief valve
in control valve (Fig. 40). If relief valve is operating prop-
erly and if lift/lower problems also exist, gear pump
should be suspected of wear and inefficiency. If steering
wheel continues to turn at end of cylinder travel (with
lower than normal effort), steering cylinder or steering
valve should be suspected of wear or damage.
8. When testing is completed, disconnect pressure
gauge from test port.
Groundsmaster 4000--D
1. Steering circuit pressure test port
1
1. Steering tower
Page 4 - - 51
1
Figure 39
2
Figure 40
2. Steering relief valve
Hydraulic System