Toro 30857 - Flush Hydraulic System

Groundsmaster 4500--D/4700--D Hydraulic SystemPage 4 -- 69
Flush Hydraulic System
IMPORTANT: Flush the hydraulic system any time
thereisa severe component failure or thesystem is
contaminated (oil appears milky, black or contains
metal particles).
IMPORTANT: Flush hydraulic system when chang-
Ing from petroleum base hydraulic fluid to a biode-
gradable fluid. Operate machine under normal
operating conditions for at least four (4) hours be-
fore draining.
1. Park machine on a level surface. Lower cutting
decks,stopengineandengageparkingbrake.Remove
key from the ignition switch.
CAUTION
Operate all hydraulic controls to relieve system
pressure and avoid injury from pressurized hy -
draulic oil. Controls must be operated with the
ignitionswitchinOFF.Removekeyfromtheigni-
tion switch.
IMPORTANT: Make sure to clean around any hy-
draulic connections that will be disconnected for
draining.
2. Drain hydraulic reservoir into a suitable container.
3. Drain hydraulic system. Drain all hoses, tubes and
components while the system is warm.
4. Change and replace both hydraulic oil filters.
5. Inspectandcleanhydraulic reservoir (seeHydraulic
ReservoirInspectionintheServiceandRepairsection).
6. Connect all hydraulic hoses, lines and components
that were disconnected while draining system.
NOTE: Use only hydraulic fluids specified in the Trac-
tion Unit Operator’s Manual. Other fluids may cause
system damage.
7. Fill hydraulic reservoir with new hydraulic fluid.
8. Disconnect wire harness connector from engine run
solenoid to prevent the engine from starting.
9. Turn ignition key switch to start and engage starter
forten(10)secondstoprimepump.Letstartercooland
then repeat cranking procedure again.
10.Connect wire harness c onnector to engine run sole-
noid.
11.Start engine and let it idle at low speed (1425 RPM)
for a minimum of two (2) minutes. Increase engine
speed to high idle (2870 RPM) for minimum of one (1)
minute under no load.
12.Raise and lower cutting decks several times. Turn
steering wheel fully left and right several times.
13.MovePTOswitchtoONtoengagecuttingdecksand
let them run for several minutes. Move PTO switch to
OFF.
14.Shut off engine and check for hydraulic oil leaks.
Check oil level in hydraulic reservoir and add correct
amount of oil if necessary.
15.Operatemachinefortwo(2) hours under normalop-
erating conditions.
16.Check condition of hydraulic oil. If the new fluid
shows any signs of contamination, repeat steps 1
through 14 again until oil is clean. If changing to biode-
gradable fluid, repeat steps 1 through 14 again at least
once and until the oil is clean.
17.Assume normal operationand follow recommended
maintenance intervals.
Hydraulic
System