Lower Cutting Units - Toro Reelmaster 6500-D Service Manual

Lower Cutting Units

The hydraulic pump assembly is driven by a coupling at-
tached to the engine flywheel. The pump assembly con-
sists of a three section gear pump, a gerotor charge
pump, and a variable displacement piston pump.
Gear pump section (P3) provides oil flow through the
steering control valve and lift manifold to all cutting unit
lift cylinders. Maximum circuit pressure (1500 PSI/104.0
bar) is limited by a relief valve in the gear pump (R3).
When the cutting units are in the raised position, flow
from the gear pump (P3) passes through the steering
control valve and into the lift manifold. All lift manifold so-
lenoid valves are de-energized and flow is directed to
the hydraulic reservoir. An electrically activated flow di-
vider (FD1) is also de-energized, preventing flow be-
tween the #4 and 5 lift cylinders.
To lower the cutting units, solenoid valves (SV3), (SV4),
(SV5), (SV6), (SV7), and (SV8) energize along with so-
lenoid valve (SV1) and flow divider (FD1). Solenoid
valve (SV2) is in its normally de-energized position, and
directs oil flow to the piston end of the lift cylinders. Hy-
draulic pressure against the piston side of the cylinder
causes the shafts to extend, and lower the cutting units.
When the solenoids and the flow divider are de-ener-
gized, the lift cylinders are held in the lowered position.
Pressure to the lift manifold can be monitored at port
(G3).
Reelmaster 6500-D/6700-D
The lowering speed of the cutting units are regulated by
several flow control valves. Location of these control
valves depend on the machine as follows:
1. On RM--6500--D machines with serial number below
280000000, two adjustable flow control valves regulate
lift cylinders #1, 4, and 5. These control valves are lo-
cated on the main lift manifold (one flow control regu-
lates lift cylinders #4 and 5). The adjustable flow control
valve that regulates lift cylinders #2 and 3 is located in
the rear of the traction unit.
2. On RM--6500--D machines with serial number above
280000000, three adjustable flow control valves in the
lift control manifold regulate the lift cylinders. One con-
trol valve regulates cylinder #1, a second controls cylin-
ders #2 and 3 and the third controls cylinders #4 and 5.
3. On RM--6700--D machines with serial number below
280000000, four adjustable flow control valves regulate
lift cylinders #1, 4, 5, 6, and 7. These control valves are
located on the main lift manifold (one flow control regu-
lates lift cylinders #4 and 5). The adjustable flow control
valve that regulates lift cylinders #2 & 3 is located in the
rear of the traction unit.
4. On RM--6700--D machines with serial number above
280000000, five adjustable flow control valves in the lift
control manifold regulate the lift cylinders. One control
valve regulates cylinder #1, the second controls cylin-
ders #2 and 3, the third controls cylinders #4 and 5, the
fourth controls cylinder #6 and the fifth controls cylinder
#7.
Page 4 - 17 Rev. F Hydraulic System