Mow And Backlap (Serial Number Under 260999999) - Toro Greensmaster 3250-D 04383 Service Manual

Mow and Backlap (Serial Number Under 260999999)

The gear pump (P1) is directly coupled to the the hydros-
tat which is driven directly by the engine. Taking its suc-
tion directly from the hydraulic reservoir, the gear pump
(P1) supplies oil flow to the hydraulic manifold block and
to the cutting reel motors.
With the engine running and the Functional Control and
Raise/Lower/Mow levers positioned so the reels will
not turn (see Operator's Manual), solenoid valve (S1) is
de--energized. S1 by--passes flow from the gear pump
(P1) directly to the hydraulic reservoir.
Mow
With the engine running and the Functional Control and
Raise/Lower/Mow levers positioned so the reels will
turn (see Operator's Manual), solenoid valve (S1) is en-
ergized. Flow is diverted to the reel motors. Gear pump
(P1) flow is routed out manifold port (MA), and to the reel
motors that are connected in series. Oil flows through
the left (M2), right (M3), and then rear reel motor (M1)
as it turns the motors in the mow direction. The oil then
returns through the manifold block, oil filter and then to
the reservoir.
Note: On traction units with serial numbers from
230000601 to 260999999, solenoid valve (S6) is ener-
gized when the cutting units are raised. This forces the
return flow from the reel motors through the .125" orifice,
putting back pressure on the reel circuit, and stopping
the reels from rotating.
Greensmaster 3250--D
On units with the optional backlap kit installed, flow
through the manifold block is different. Oil flow from port
(P1) flows through the 11 position reel speed control
valve (FC1). Flow across the speed control valve is
pressure compensated by the logic cartridge valve
(LC1). The logic cartridge valve maintains a pressure
differential of 75 PSI (5.2 bar) across the speed control
valve. Any excess flow above what the speed control
valve is set for is by--passed to the reservoir through the
logic cartridge valve. With the backlap valve (RD1) in the
mow position, oil flows through the valve, out port (MA),
and to the reel motors that are connected in series.
Oil flows through the left (M2), right (M3), and then rear
reel motor (M1) as it turns the motors in the mow direc-
tion. The oil then returns through the manifold block and
oil filter and then to the reservoir.
Backlap
On machines with backlap capabilities, backlapping op-
eration is the same as mowing operation, except for the
position of the backlap valve (RD1). When the backlap
valve is in the backlap position, oil flows through the
rear (M1), right (M3), and then left (M2) reel motor as it
turns the motors in the backlap direction.
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Hydraulic System (Rev. I)