Toro Greensmaster 3120 Service Manual page 108

Steering/Lift Circuit Testing – Gear Pump (P3) Flow and Circuit
Relief Valve Test (continued)
Hydraulic System: Testing the Hydraulic System
C. Record tester pressure and flow readings under load.
D. Open flow control valve fully.
E. The under load test flow reading (step B) should not drop more than
15% when compared to the pump at no load test flow reading (step A). A
difference in flow of more than 15%, or the inability to achieve specified
pressure may indicate a restriction in the pump intake line, or that the
gear pump (P3) is worn and should be repaired or replaced.
10. Test the circuit relief valve as follows:
When performing the test, do not allow the system pressure to
exceed 8300 kPa (1400 PSI).
Hold steering wheel at full lock only long enough to obtain a
system pressure reading.
A. Open the circuit relief valve via the steering system. Watch the pressure
gauge on the tester and turn the steering wheel completely in one
direction. The circuit relief valve should open just after the rear wheel
gets to the full lock position. Record the pressure at which the relief valve
opens.
B. Open the circuit relief valve via the lift system. Watch the pressure
gauge on the tester and move the joystick control to the
Momentarily hold the joystick with the cutting units fully raised causing
the circuit relief valve to open. Record the pressure at which the relief
valve opens.
C. Set the joystick to the
Note: The circuit relief valve is in series with charge relief valve. Charge
relief pressure will affect the circuit relief pressure.
D. The circuit relief valve pressure should be 7300 to 8600 kPa (1050 to
1250 PSI) higher than the charge relief valve pressure (e.g. if the
charge relief valve pressure is 414 kPa (60 PSI), the circuit relief valve
pressure should be from 7653 to 9032 kPa (1110 to 1310 PSI).
Note: The Lowering Cutting Units Relief Valve Test is performed with the
tester installed in its current location. Refer to
– Lowering Cutting Units Relief Valve Test (page 4–63)
information.
11. When testing is complete, remove tester and connect hose to pump fitting.
12. Check fluid level in hydraulic tank and adjust as necessary; refer to traction
unit Operator's Manual.
CAUTION
IMPORTANT
position and turn the engine OFF.
NEUTRAL
Page 4–62
position.
RAISE
Steering/Lift Circuit Testing
for additional
Greensmaster 3120
17230SL Rev C