Service Manual

Groundsmaster 360 Hydraulic SystemPage 4 − 45
The Rear Wheel Motor Efficiency Test should be per-
formed if a traction circuit problem is identified. This test
will determine if a rear wheel motor has excessive inter-
nal leakage and wear.
NOTE: Over a period of time, a wheel motor can wear
internally. A worn motor may bypass oil internally caus-
ing 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 Rear Wheel Motor Efficiency
Test:
IMPORTANT: Traction circuit flow for the
Groundsmaster 360 is approximately 15 GPM (57
LPM). Use 40 GPM Hydraulic Tester #AT40002 (pres-
sure and flow) for this test (see Special Tools in this
chapter).
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
lowered and off. Apply parking brake and make sure en-
gine 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.
WARNING
Before jacking up the machine, review and follow
Jacking Instructions in Chapter 1 − Safety.
5. Jack up and support the front wheels off the ground
to allow flow through the front wheel motors.
6. Chock rear wheels to prevent wheel rotation.
7. Thoroughly clean area surrounding traction circuit
hoses on top of transmission (Fig. 33 or 34). Determine
which rear wheel motor is to be tested.
Figure 34
Port C
Port D
Port B
Port A
Balancing Hose
Balancing Hose
4WD Machine
8. Disconnect hydraulic hose from transmission pump
outlet fitting for rear wheel motor to be tested (Fig. 33 or
34):
Wheel Motor to be Tested
Pump Outlet
Right Side Rear Motor Port A
Left Side Rear Motor Port C
9. Install 40 GPM hydraulic tester (pressure and flow)
in series between the pump outlet fitting and the discon-
nected 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.
10.Disconnect balancing hose from transmission fitting
closest to transmission pump outlet fitting for rear wheel
to be tested (Fig. 33 or 34). Install steel cap on fitting and
steel plug in balancing hose.
11.Start engine and run at low idle speed (1300 RPM).
Check for any hydraulic leakage from test connections
and correct before proceeding with test.
12.With engine running, move throttle so engine is run-
ning at high idle speed (3100 to 3150 RPM). Use a pho-
totac to measure engine speed.
CAUTION
Use extreme caution when performing test. The
rear wheels will be trying to move the machine
forward.
13.While sitting in operator seat, and with brakes firmly
applied to prevent the rear wheels from rotating, slowly
depress the traction pedal in the forward direction until
1000 PSI (69 bar) is displayed on the tester pressure
gauge.
Hydraulic
System