Toro Groundsmaster 4700-D Service Manual page 55

Raise Cutting Decks: Groundsmaster 4500- -D
A four section gear pump is coupled to the piston (trac-
tion) pump. Gear pump section P3 supplies hydraulic
flow to both the lift control manifold and the steering con-
trol valve. Hydraulic flow from this pump section is deliv-
ered to the circuits through a proportional flow divider
located in the fan control manifold. Maximum lift/lower
circuit pressure is limited to 1600 PSI (110 bar) by a relief
valve (R1) in the lift control manifold. Lift circuit pressure
can be monitored at test fitting G1 on the lift control man-
ifold.
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 gear pump sec-
tion P3 bypasses the lift cylinders through the lift control
manifold solenoid valve S5 and proportional relief valve
PRV which are de--energized. Return flow from the
manifold is routed to the oil filter and traction charge cir-
cuit.
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
center five (5) deck lift cylinders. The oil flow causes the
lift cylinders to retract and raise the five (5) cutting decks.
Two (2) orifices in the junction manifold control the rais-
ing speed of the #2 and #3 decks.
When the deck switch is released, solenoid valve S5 is
de--energized and the lift cylinders and cutting decks are
held in position.
Groundsmaster 4500--D/4700--D
1. Lift switch (#1 to #5)
#4
GM- -4500 CUTTING DECK LOCATIONS
Page 4 - - 21
1
Figure 14
#1 #5
#2 #3
Figure 15
Hydraulic System