Cutting Unit (Or Attachment) Lift/Lower Problems - Toro Groundmaster Series Service Manual

Cutting Unit (or attachment) Lift/Lower Problems

Problem
Lift cylinders will not raise or raise
slowly.
Lift cylinders raise but will not stay up.
NOTE: Lift cylinders cannot provide an
absolutely perfect seal. The lift arms
will eventually lower if left supporting
an attachment in the raised position
during storage.
Lift cylinders will not lower.
Troubleshooting: Cutting Unit (or attachment) Lift/Lower
Problems
Possible Cause
Engine speed is too low.
Lift arms are binding, worn or damaged.
The hydraulic fluid level in the hydraulic
tank is low (other hydraulic circuit
performance is affected as well).
An electrical problem exists in the
solenoid valve (SV1) circuit.
Solenoid valve (SV1) in the main
manifold is stuck, leaking or faulty.
Relief valve (R4) in the steering control
valve is faulty.
Lift cylinder circuit pressure is low
(traction charge and steering circuits
affected as well).
Solenoid valve (SV2) in the main
manifold is stuck, leaking or faulty.
A lift cylinder is leaking internally.
An electrical problem exists in the
solenoid valve (SV2) circuit.
Solenoid valve (SV2) in the main
manifold is stuck, leaking or faulty.
Page 3–20
Corrective Action
Increase engine speed.
Inspect lift components and repair or
replace if necessary.
Adjust the hydraulic fluid level.
Test the solenoid valve coil (SV1) and
replace if necessary.
Test the machine wire harness solenoid
valve (SV1) circuit.
Clean the solenoid valve and replace
the seals.
Replace the solenoid valve if necessary.
Verify relief valve (R4) operation; refer
to Testing the Steering and Lift Circuit
– Steering Cylinder and Circuit Relief
Valve in the Hydraulic System chapter
of this manual.
Verify charge pressure; refer to Testing
the Traction Circuit – Charge Pressure
in the Hydraulic System chapter of this
manual.
Verify gear pump (P2) performance;
refer to Testing the Steering and Lift
Circuit – Gear Pump (P2) Flow and
Circuit Relief Valve in the Hydraulic
System chapter of this manual.
Clean the valve and replace the seals.
Replace the valve if necessary.
Test and repair or replace the hitch
cylinder if necessary.
Test the solenoid valve coil (SV2) and
replace if necessary.
Test the machine wire harness solenoid
valve (SV2) circuit.
Clean the solenoid valve and replace
the seals.
Replace the solenoid valve if necessary.
Groundsmaster ® 3200, 3300 and 3310
19240SL Rev A