Mow Circuit Problems - Toro Groundsmaster 4300-D Service Manual

Traction Circuit Problems (continued)
Problem
The wheel motor does not hold load in the N
Note: The machine may not be completely stationary if
parked on an incline without the parking brake engaged.
A single-wheel motor turns while unloaded, but slows down
or stops when the load is applied.

Mow Circuit Problems

Problem
All the 3 front cutting deck motors do not operate but rear
cutting deck motors operate.
Both rear cutting deck motors do not operate but front cutting
deck motors operate.
A single cutting deck motor does not operate or rotates
slowly.
Groundsmaster ® 4300-D
16226SL Rev C
position. • The charge pressure is low.
EUTRAL
• The check valves in the piston (traction) pump are damaged.
• The valve plate(s) in the piston (traction) pump is worn or
damaged.
• The wheel motor is worn or damaged.
Note: If 1 traction circuit component has internal wear or
damage, it is possible that the other traction components
are also damaged.
• The piston (traction) pump bypass valve is open or leaking.
• The wheel motor is worn or damaged.
Note: If 1 traction circuit component has internal wear or
damage, it is possible that the other traction components
are also damaged.
• The solenoid valve PRV2 on deck control manifold is
damaged.
Note: The solenoid valves PRV1 and PRV2 are identical and
can be reversed for testing purposes.
• An electrical problem exists that prevents PRV2 solenoid
coil on deck control manifold from being energized (refer to
Troubleshooting (page 5–24)
and Wire Harness Drawings/Diagrams in
A–1)).
• One or more front deck spindle is binding.
• The gear pump section (P2) is worn or damaged.
• The solenoid valve PRV1 on deck control manifold is
damaged.
Note: The solenoid valves PRV1 and PRV2 are identical and
can be reversed for testing purposes.
• An electrical problem exists that prevents PRV1 solenoid
coil on deck control manifold from being energized (refer to
Troubleshooting (page 5–24)
and Wire Harness Drawings/Diagrams in
A–1)).
• One or more rear deck spindle is binding.
• The gear pump section (P1) is worn or damaged.
• The cutting deck motor is worn or damaged.
• The cross-over relief valve in the cutting deck motor is stuck
or damaged.
Note: If appropriate, transfer a suspected damaged motor
to another cutting deck. If problem follows the motor, motor
needs to be repair or replacement.
Page 4–41
Possible Causes
Possible Causes
or the Electrical Schematic
Appendix A (page
or the Electrical Schematic
Appendix A (page
Hydraulic System: Troubleshooting