Toro Groundsmaster 4000-D Service Manual page 63

Problem
Traction power is lost or unit will not
operate in either direction.
Four wheel drive will not engage.
Four wheel drive will not disengage.
No cutting decks will operate.
One cutting deck will not operate.
All cutting decks operate slowly.
Cutting deck stops under load.
Groundsmaster 4000--D
Possible Causes
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 hydraulic 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 hydraulic manifold is faulty.
Cartridge valve in 4WD manifold is damaged or sticking.
Electrical problem exists (see Chapter 5 -- Electrical System).
Gear pump or its coupler is damaged (NOTE: other hydraulic circuits
impacted as well).
Electrical problem exists (see Chapter 5 -- Electrical System).
System pressure to the affected deck is low.
Woodruff key on affected deck motor is damaged.
Solenoid valve (S) in deck manifold is faulty.
Cartridge valve in deck manifold is damaged or sticking.
Deck motor or gear pump section is damaged.
Engine RPM is low.
Deck motor or gear pump sections are damaged.
Relief valve in deck manifold is by--passing.
Deck motor has internal leakage (by--passing oil).
Cutting deck gear pump section is inefficient.
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