Troubleshooting; Troubleshooting - Toro Groundsmaster 4000-D Service Manual

Troubleshooting

The charts that follow contain suggestions to assist in
troubleshooting. There may possibly be more than one
cause for a machine malfunction.
Refer to the Testing section of this Chapter for precau-
tions and specific test procedures.
Problem
Hydraulic system operates hot.
NOTE: An indication that the hy-
draulic system is operating at exces-
sive temperatures would be frequent
reversing of the cooling fan and a
normal engine coolant temperature.
Hydraulic oil in reservoir foams.
Machine operates in one direction
only.
Traction pedal is sluggish.
Machine travels too far before stop-
ping when the traction pedal is re-
leased.
Hydraulic System
NOTE: When troubleshooting traction problems on the
Groundsmaster 4000--D, if a problem exists in both
4WD and transport speeds, consider a faulty compo-
nent that affects the entire traction circuit (e.g. charge
circuit, relief valves, piston pump, front wheel motors).
If the problem exists in 4WD but not in transport, consid-
er a problem in the 4WD traction system (e.g. rear axle
motor, 4WD manifold).
Possible Cause
Engine RPM is too low.
Brakes are applied or sticking.
Hydraulic reservoir oil level is low.
Hydraulic oil is contaminated or the wrong type.
Piston pump by--pass valve is open or damaged.
Cooling system is not operating properly.
Charge pressure is low.
Traction circuit pressure is incorrect.
Pump(s) or motor(s) are damaged.
Hydraulic reservoir oil level is low.
Wrong type of oil is in the hydraulic system.
Air is leaking into a pump suction line.
Traction control linkage is faulty.
Traction relief valve is defective.
Traction control linkage is stuck or binding.
Charge pressure is low.
Piston (traction) pump servo control valve orifices are plugged or
damaged.
4WD manifold PD1 and PD2 pilot directional valves seals are leaking
or damaged.
Traction linkage is out of adjustment.
Charge pressure is low.
Piston (traction) pump servo control valve orifices are plugged or da-
maged.
Traction pedal does not return to neutral.
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