Toro Groundsmaster 4000-D Service Manual page 69

Traction Circuit Problems
Problem
Machine operates in one direction
only.
Traction pedal is sluggish.
Machine travels too far before stop-
ping when the traction pedal is re-
leased.
Traction power is lost or machine will
not operate in either direction.
Four wheel drive will not engage.
NOTE: Low (4WD) will not engage
when the cutting decks are lowered.
Four wheel drive will not disengage.
Groundsmaster 4000--D/4010--D
Possible Cause
Traction control linkage is faulty.
Traction relief valve is faulty.
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.
Traction pedal does not return to neutral position.
Charge pressure is low.
Piston (traction) pump servo control valve orifices are plugged or
damaged.
Hydraulic reservoir oil level is low.
Piston pump by--pass valve is open or damaged.
Charge pressure is low.
Traction circuit pressure is low.
Front wheel motor couplers are damaged.
Electrical problem exists (see Chapter 5 -- Electrical System).
Solenoid valve (SV) in 4WD manifold is faulty.
Cartridge valve(s) in 4WD manifold is faulty.
Drive gear on rear axle motor or driven gear for rear axle is loose or
damaged.
Rear axle motor is damaged.
Electrical problem exists (see Chapter 5 -- Electrical System).
Solenoid valve (SV) in 4WD manifold is faulty.
Cartridge valve in 4WD manifold is damaged or sticking.
Page 4 - - 31 Hydraulic System