Toro Groundsmaster 4500-D Service Manual page 61

Raise Cutting Decks: Groundsmaster 4500- D
A four section gear pump is coupled to the piston (trac-
tion) pump. The third gear pump section supplies hy-
draulic flow to both the lift control manifold and the
steering control valve. Hydraulic flow from this pump
section is delivered to the circuits through a proportional
flow divider located in the fan control manifold. Maxi-
mum lift/lower circuit pressure is limited to 1600 PSI (110
bar) by a relief valve (RV) in the lift control manifold. Lift
circuit pressure can be monitored at test fitting G1 on the
lift control manifold.
On the Groundsmaster 4500- D, a single lift switch on
the console arm is used to raise and lower the five (5)
cutting decks (Fig. 14).
When the cutting decks are in a stationary position (not
raising or lowering), lift circuit flow from the third gear
pump section bypasses the lift cylinders through the lift
control manifold solenoid valve S5 and proportional re-
lief valve TS which are de- energized. Return flow from
the manifold is routed to the oil filter and traction charge
circuit.
NOTE: The operator must be in the operator seat in or-
der to raise the cutting decks.
Cutting Deck Raise
To raise the five (5) cutting decks on a Groundsmaster
4500- D, the rear of the lift switch is depressed. The
switch acts as an input to the TEC- 5002 controller which
then provides an electrical output to solenoid valve S5
in the lift control manifold. Energized solenoid valve S5
shifts to allow a passage for oil flow to the rod ends of the
five (5) deck lift cylinders. The oil flow causes the lift cyl-
inders to retract and raise all of the cutting decks. The
junction manifold orifice leading to the #1 deck is by-
passed during deck raising.
Groundsmaster 4500- D/4700- D
1
1. Console arm
#4
GM- 4500 CUTTING DECK LOCATIONS
Page 4 - 21
Rev. A
2
Figure 14
2. Lift switch
#1 #5
#2 #3
Figure 15
Hydraulic System