Lift Circuit Problems - Toro Groundsmaster 4000-D Service Manual

Lift Circuit Problems

Problem
Cutting decks will not raise.
NOTE: Seat must be occupied in or-
der to raise cutting decks.
Cutting decks raise, but will not stay
up.
NOTE: Lift cylinders cannot provide
an absolutely perfect seal. A cutting
deck will eventually lower if left in the
raised position during storage.
Cutting decks will not lower.
NOTE: To lower a cutting deck, the
seat must be occupied and the trac-
tion speed must be in the LOW
(mow) position.
Hydraulic System
Possible Cause
Engine RPM is too low.
Hydraulic oil level in reservoir is low (NOTE: Other hydraulic systems
are affected as well).
Solenoid valve (S1) in combination manifold is faulty.
Electrical problem exists (see Chapter 5 -- Electrical System).
Lift arm pivots are binding.
Lift/lower relief valve in combination manifold is stuck.
Lift cylinder(s) is (are) damaged.
Gear pump section for lift circuit is worn or damaged (NOTE: A worn
or damaged gear pump section will also affect the steering, engine
cooling fan motor and traction charge circuits).
Lift circuit hydraulic lines or fittings are leaking.
Combination manifold cartridge valve(s) for lift/lower circuits has
damaged seals or is faulty.
Lift cylinder for affected deck is damaged.
Lift arm pivots are binding.
Electrical problem exists (see Chapter 5 -- Electrical System).
Solenoid valve (S1) in combination manifold is faulty.
Counterbalance pressure is excessive.
Lift cylinder for affected deck is damaged.
Page 4 - - 36 Groundsmaster 4000--D/4010--D