Traction Circuit Problems - Toro Greensmaster 3150 Service Manual

Traction Circuit Problems

Problem
Neutral is difficult to find or machine
operates in one direction only.
Traction response is sluggish.
No traction exists in either direction.
Wheel motor will not turn.
Wheel motor will not hold load in
neutral.
NOTE: The piston (traction) pump used on Green-
smaster 3150 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.
Hydraulic System
Possible Cause
External control linkage is misadjusted, disconnected, binding or
damaged.
Piston (traction) pump is worn or damaged (see Piston (Traction)
Pump Flow Test in the Testing section of this chapter).
Hydraulic oil is very cold.
Brakes are applied or are incorrectly adjusted.
Piston pump by--pass valve is open or defective.
Charge pressure is low (see Charge Pressure Relief Valve Pres-
sure Test in the Testing section of this chapter).
Piston (traction) pump relief valves are leaking or damaged.
Piston (traction) pump or wheel motor(s) are worn or damaged (see
Piston (Traction) Pump Flow and Wheel Motor Efficiency Tests in
the Testing section of this chapter).
Brakes are applied or are incorrectly adjusted.
Hydraulic reservoir oil level is low (other hydraulic circuits affected
as well).
Piston pump by--pass valve is open.
Charge pressure is low (see Charge Pressure Relief Valve Pres-
sure Test in the Testing section of this chapter).
Wheel motor(s) are worn or damaged (see Wheel Motor Efficiency
Test in the Testing section of this chapter).
Piston (traction) pump is worn or damaged (see Piston (Traction)
Pump Flow Test in the Testing section of this chapter).
Brakes are binding.
Key on wheel motor shaft is sheared or missing.
Wheel motor is damaged.
Make up fluid from charge pump is not available.
Piston (traction) pump relief valves are leaking or damaged.
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