Toro Sand Pro 5020, Service Manual

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Sand Pro 2020/3020/5020 Hydraulic System (Rev. A) Page 4 -- 17
Troubleshooting (cont.)
Problem Possible Cause
System operates in a jerky manner
when starting.
External control linkage is misadjusted, disconnected, binding, or
damaged.
Charge valve in hydrostat is defective.
Acceleration valves in hydrostat are defective.
No traction exists in either direction,
or loss of power.
Brake is not released.
Hydraulic oil is very cold.
Oil level in tank is low.
External control linkage is misadjusted, disconnected, binding, or
damaged.
Charge pressure is low due to the following possible causes:
Oil filter is clogged.
Charge relief valve is defective.
Implement relief valve is defective.
Charge pump is defective.
Traction pump outlet pressure is low due to the following possible
causes:
Accelerator valves are defective.
Charge check valves are defective.
Traction pump is worn or defective.
Wheel motor(s) are worn or damaged.
Wheel motor will not hold load in
neutral.
Make up fluid from charge pump is not available.
Charge check valves are damaged.
Attachment will not lift or lifts slowly. Engine speed is too low.
Charge pump is damaged.
Lift cylinder linkage is binding or broken.
Lift cylinder bushings bind.
Tank oil level is low.
Charge pump pressure or flow is insufficient.
Implement relief valve is stuck open.
Lift cylinders leak internally.
Hydraulic Systems