Lift/Lower Circuit: Raise - Toro Groundsmaster 360 Service Manual

Lift/Lower Circuit: Raise

Hydraulic System: Hydraulic Flow Diagrams
A single-section gear pump is directly coupled to the transmission which is driven
by the engine. This gear pump supplies hydraulic flow for both the steering and
lift/lower circuits. The gear pump flow is routed to the steering control valve
first so that the steering circuit has priority. The pump takes its suction from
the hydraulic tank.
When the deck lift switch is in its neutral state, flow from the gear pump bypasses
the lift cylinder and is routed through the deck lift manifold directly to the oil
cooler and then to the transmission. The transmission case drain allows the
hydraulic fluid to return to the hydraulic tank.
Note: If the deck lift switch is pressed to the R
wheel is being turned, the lift speed will be reduced.
When the deck lift switch is pressed to the R
valves (S1 and S2) in the deck lift manifold are energized to cause the valves
to shift. The energized solenoid valve S2 prevents the gear pump flow from
bypassing the lift cylinder. The energized solenoid valve S1 allows hydraulic fluid
flow from the gear pump to the barrel end of the lift cylinder. The lift cylinder
extends, causing the cutting deck to raise. The fluid displaced from the rod
end of the lift cylinder is routed to the oil cooler, transmission, and then to the
hydraulic tank. An orifice fitting in the deck lift manifold controls the speed of the
lift cylinder while raising the cutting deck.
The load on the lift cylinder causes lift circuit pressure to increase. If lift circuit
pressure reaches 12,500 kPa (1,800 psi), the relief valve in the gear pump shifts
to allow pump flow to return to the hydraulic tank.
When the deck lift switch is released from the R
valves (S1 and S2) in the deck lift manifold are de-energized. The de-energized
solenoid valve S2 allows the gear pump flow to bypass the lift cylinder, returning
to the oil cooler, transmission, and then to the hydraulic tank. The de-energized
solenoid valve S1 prevents the hydraulic flow to and from the lift cylinder to keep
the cutting deck in the raised position.
AISE
AISE
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position while the steering
position and held, the solenoid
position, both the solenoid
AISE
Groundsmaster 360
16225SL Rev C