Service And Repairs 4 - Toro Groundsmaster 4000-D Service Manual

Procedure for Steering Circuit Relief Pressure Test
1. Make sure hydraulic oil is at normal operating tem-
perature by operating the machine under load for
approximately ten (10) minutes. Make sure the hydrau-
lic 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. Locate steering circuit pressure test port and con-
nect a 5000 PSI (350 bar) pressure gauge onto test port.
A. On Groundsmaster 4000--D machines, the test
port is located on the steering supply hydraulic tube
under the front of the machine (Fig. 48).
B. On Groundsmaster 4010--D machines, the test
port is located on the steering supply hydraulic tube
under the operator seat (Fig. 49).
4. Start the engine and move throttle to high idle engine
speed (2870 RPM).
IMPORTANT: Hold steering wheel at full lock only
long enough to get a system relief pressure reading.
Holding the steering wheel against the stop for an
extended period can damage the steering control
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.
Groundsmaster 4000--D/4010--D
7. If pressure is incorrect, inspect steering relief valve
in steering control valve (see Steering Control Valve in
the Service and Repairs section of this chapter). If relief
valve is operating properly and if lift/lower problems also
exist, flow divider in fan manifold and/or gear pump
(third section) should be suspected of wear and ineffi-
ciency. If steering wheel continues to turn at end of cylin-
der travel (with lower than normal effort), steering
cylinder or steering control valve should be suspected
of wear or damage.
8. When testing is completed, disconnect pressure
gauge from test port.
1
1. Steering circuit pressure test port (GM4000- -D)
1
1. Steering circuit pressure test port (GM4010- -D)
Page 4 - - 61
Figure 48
Figure 49
Hydraulic System