Lift Circuit Problems - Toro Reelmaster 5210 Service Manual

Lift Circuit Problems

Problem
Single cutting unit lifts slowly or not
at all
Cutting units raise, but will not re-
main in the raised position
(NOTE: Lift cylinders and control
manifold check valves cannot pro-
vide an absolutely perfect seal. The
cutting units will eventually lower if
left in the raised position)
None of the cutting units will raise or
lower
None of the front cutting units will
raise or lower but the rear cutting
units will raise and lower
Neither of the rear cutting units will
raise or lower but the front cutting
units will raise and lower
Reelmaster 5010 Series
Possible Cause
Cutting unit has excessive debris buildup.
Lift arm or lift cylinder is binding.
Pilot piston in lift control manifold is stuck or damaged.
Lift cylinder leaks internally.
Flow control orifice in lift control manifold for the affected cutting
unit is plugged or damaged.
Lift cylinder leaks internally.
Check valve in lift control manifold (CV1, CV4, CV5 and CV23) and
solenoid valve (SV1 and SV3) leaks.
Pilot piston in lift control manifold is stuck and is preventing check
valve from seating.
Oil level in hydraulic reservoir is low (other hydraulic systems af-
fected as well).
MR1 and/or MR2 in lift control manifold are in the backlap position.
Solenoid valve SVRV on lift control manifold is faulty.
An electrical problem exists that prevents SVRV solenoid coil on
the lift control manifold from being energized (see Troubleshooting
in Chapter 5 -- Electrical System).
Gear pump section (P4) is worn or damaged.
Solenoid valve SV1 on lift control manifold is faulty.
An electrical problem exists that prevents SV1 solenoid coil on the
lift control manifold from being energized (see Troubleshooting in
Chapter 5 -- Electrical System).
Solenoid valve SV3 on lift control manifold is faulty.
An electrical problem exists that prevents SV3 solenoid coil on the
lift control manifold from being energized (see Troubleshooting in
Chapter 5 -- Electrical System).
Flow control orifice in lift control manifold for the rear cutting units
(C23 or C23L) is plugged or damaged.
Check valve in lift control manifold for the rear cutting units (CV23)
is stuck or damaged.
Page 4 - - 25 Hydraulic System (Rev. C)