Toro Groundsmaster 7200 Service Manual page 69

The Wheel Motor Efficiency Test should be performed
if a traction circuit problem is identified. This test will de-
termine if a wheel motor has excessive internal leakage
and wear.
NOTE: Over a period of time, a wheel motor can wear
internally. A worn motor may by–pass oil to its case drain
causing the motor to be less efficient. Eventually,
enough oil loss will cause the wheel motor to stall under
heavy load conditions. Continued operation with a worn,
inefficient motor can generate excessive heat, cause
damage to seals and other components in the hydraulic
system and affect overall machine performance.
Procedure for Wheel Motor Efficiency Test:
1. Make sure hydraulic oil is at normal operating tem-
perature. Also, make sure that traction drive is correctly
adjusted for the neutral position.
WARNING
Before disconnecting or performing any work on
the hydraulic system, all pressure in the system
must be relieved. See Relieving Hydraulic System
Pressure in the General Information section.
2. Park machine on a level surface with the cutting deck
(or implement) lowered and off. Apply parking brake and
make sure engine is off.
3. Read Precautions for Hydraulic Testing listed at the
beginning of this section.
4. Attach a heavy chain to the rear of the machine frame
and an immovable object to prevent the machine from
moving during testing. As an alternative, machine can
be raised and supported with jack stands so that both
rear wheels are off the ground.
5. Disconnect wire harness connector from parking
brake switch (see Parking Brake Switch in the Compo-
nents section of Chapter 5 – Electrical System). Install
jumper wire across harness connector terminals to al-
low traction circuit operation with the parking brake ap-
plied.
6. Thoroughly clean transmission area surrounding
traction circuit hoses on top of transmission (Fig. 18).
Determine which wheel motor is to be tested.
7. Disconnect hydraulic hose from transmission pump
outlet fitting for wheel motor to be tested (Fig. 18):
Wheel Motor to be Tested
Right Side Motor
Left Side Motor
Groundsmaster 7200/7210
8. Install hydraulic tester (pressure and flow) in series
between the pump outlet fitting and the disconnected
hose. Make sure that the tester flow arrow points from
the pump outlet and toward the hose. Make sure the
flow control valve on the tester is fully open.
9. Start engine and run at low idle speed (1500 to 1650
RPM). Check for any hydraulic leakage from test con-
nections and correct before proceeding with test.
IMPORTANT: Do not run engine at full speed when
performing this test using Toro Hydraulic Tester
(Pressure and Flow) (TOR214678). Traction pump
output at full engine speed can damage hydraulic
tester.
10.Using a phototac to measure engine speed, move
throttle so engine speed is 2800 RPM (not full speed).
Make sure parking brake is applied to keep wheel from
rotating during test.
Use extreme caution when performing test. The
rear wheel that is being tested will be trying to
move the machine forward.
11. While sitting in operator seat, slowly push traction
control lever for wheel motor being tested in the forward
direction until 1000 PSI (69 bar) is displayed on the test-
er pressure gauge.
12.Wheel motor internal leakage will be shown on the
tester flow meter in GPM (LPM).
13.Return traction control lever to the neutral position.
Shut off engine and record test results. Rotate wheel
and retest. Testing of wheel motor leakage in three (3)
different wheel positions will provide the most accurate
test results.
14.Flow should be less than 1.5 GPM (5.7 LPM) for the
tested wheel motor. If specification is not met, the
tested wheel motor needs to be repaired or replaced.
15.Relieve hydraulic system pressure (see Relieving
Hydraulic System Pressure in the General Information
section). Disconnect tester from pump outlet fitting and
hydraulic hose. Connect hose to pump fitting.
16.If other wheel motor requires testing, complete steps
6 to 15 for the remaining motor.
17.After testing is completed, remove jumper wire from
parking brake harness connector. Connect wire harness
Pump Outlet
to parking brake switch (see Parking Brake Switch in the
Port A
Components section of Chapter 5 – Electrical System).
Port C
Make sure that brake switch operation is correct.
Page 4 – 33
CAUTION
Hydraulic System