Toro Groundsmaster 3280-D Service Manual page 154

Test Procedure (continued)
Hydraulic System: Testing the Hydraulic System
3. Raise and support the operator seat, remove the seat plate to get access to
the hydraulic pump assembly.
4. Clean the junction of the hydraulic tube and left side elbow fitting on the
charge pump. Disconnect the hydraulic tube from the left side of the pump
fitting.
Ensure that the fluid flow indicator arrow on the flow meter is
showing that the fluid will flow from the hydraulic tube, through the
tester, and into the charge pump.
5. Install a tester with the pressure gauge and flow meter in series between the
charge pump fitting and the disconnected tube. Ensure that the flow control
valve on the tester is fully open.
6. Ensure that the hydraulic fluid is at normal operating temperature by
operating the machine for at least 10 minutes.
7. Ensure that the traction pedal is in the N
stationary, and parking brake is set.
8. Start the engine and run it at low-idle speed (1,500 to 1,650 rpm). Check for
hydraulic-fluid leaks from the test connections and correct before continuing
the test.
9. With the engine running, move the throttle to full speed (3,100 to 3,250 rpm)
position. Use a tachometer to check that the engine speed is correct.
10. Verify the pump flow at No Load as follows:
A. Record the tester pressure and flow readings at no load. Unrestricted
pump output should be approximately 14 L/minute (3.7 gallons/minute).
11. Verify the pump flow Under Load as follows:
Do not close the tester valve fully when performing this test. In this
test, the hydraulic tester is positioned in an unprotected part of the
steering circuit.
Pump damage can occur if the fluid flow is fully restricted by fully
closing the tester flow control valve.
A. Monitor the tester pressure gauge carefully while you slowly close the
flow control valve until you get 5,790 kPa (840 psi).
B. Record the tester pressure and flow readings under load.
12. Move the throttle to low speed (1,500 to 1,650 rpm) position and shut off
the engine.
13. The under load test flow reading (step 11B) should not drop more than 15%
when compared to the no load test flow reading (step 10A). A difference in
flow of more than 15%, or the inability to achieve specified pressure may
indicate:
A. A restriction in the pump inlet line.
IMPORTANT
EUTRAL
CAUTION
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position, steering wheel is
Groundsmaster ® 3280-D/3320
05138SL Rev B