Traction Circuit Problems - Toro Greensmaster 3120 Service Manual

Traction Circuit Problems

Problem
The traction response is sluggish.
Neutral is difficult to find or machine operates in one direction
only.
No traction exists in either direction.
The wheel motor does not turn.
While on level ground, the wheel motor does not hold load in
the N position.
EUTRAL
Note: The piston (traction) pump used on Greensmaster 3120 machines is equipped with relief valves
for both the forward and reverse direction. Due to engine output, it is unlikely that traction pressure will
reach relief valve settings. If, however, a piston pump relief valve is leaking or otherwise faulty, traction
performance would be affected.
Greensmaster 3120
17230SL Rev C
The hydraulic fluid is very cold.
The transmission bypass valve(s) is open or damaged.
The brake is dragging or binding.
The traction pump relief valves are leaking or damaged.
The charge pressure is low; refer to Charge Pressure Relief
Valve Pressure Test in the Testing section of this chapter.
The traction pump or wheel motor(s) is worn or damaged.
Note: If a traction circuit component has internal wear or
damage, it is possible that the other traction components
are also damaged.
The external control linkage is incorrectly adjusted,
disconnected, binding, or damaged.
The orifice in the traction pump check valve(s) is plugged.
The traction pump is worn or damaged.
The brakes are applied or are incorrectly adjusted.
The hydraulic-fluid level in the hydraulic tank is low (other
hydraulic circuit performance is affected as well).
The transmission bypass valve is open.
The charge pressure is low; refer to Charge Pressure Relief
Valve Pressure Test in the Testing section of this chapter.
The traction pump or wheel motor(s) is worn or damaged.
Note: If a traction circuit component has internal wear or
damage, it is possible that the other traction components
are also damaged.
Brakes are binding.
Key on wheel motor shaft is sheared or missing.
The wheel motor is worn or damaged.
Note: If a traction circuit component has internal wear or
damage, it is possible that the other traction components
are also damaged.
The make-up fluid from the charge pump is not available.
The check valves in the transmission are damaged.
The traction pump relief valves are leaking or damaged.
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Possible Causes
Hydraulic System: Troubleshooting