Toro Groundsmaster 4500-D, Service Manual

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Groundsmaster 4500--D/4700--D Hydraulic System (Rev. A) Page 4 -- 54
Charge Hydraulic System
NOTE: When initially starting the hydraulic system with
new or rebuilt components such as motors, pumps, or
lift cylinders, it is important that the hydraulic system be
charged properly. Air must be purged from the system
and its components to reduce the chance of damage.
IMPORTANT: Change hydraulic oil filter whenever
hydraulic components are repaired or replaced.
1. Park machine on a level surface. Lower cutting units,
stop engine, and engage parking brake. Remove key
from the ignition switch.
2. Make sure all hydraulic connections, lines, and com-
ponents are secured tightly.
3. If component failure was severe or the system is con-
taminated, flush and refill hydraulic system and tank
(see Flush Hydraulic System).
4. Make sure hydraulic reservoir is full. Add correct hy-
draulic oil if necessary (see Traction Unit Operator’s
Manual).
5. Disconnect engine run solenoid lead to prevent the
engine from starting.
6. Check control rod to the piston (traction) pump for
proper adjustment, binding, or broken parts.
7. Make sure traction pedal and lift control lever are in
the neutral position. Turn ignition key switch; engage
starter for fifteen (15) seconds to prime the traction and
gear pumps.
8. Reconnect engine run solenoid lead.
WARNING
Before jacking up the machine, review and follow
Jacking Instructions in Chapter 1 -- Safety.
9. Raise one front and one rear wheel off the ground,
and place support blocks under the frame. Chock re-
maining wheels to prevent movement of the machine.
10.Make sure traction pedal and lift control lever are in
neutral . Start engine and run it at low idle (1300 rpm) .
The charge pump should pick up oil and fill the hydraulic
system. If there is no indication of fill in 30 seconds , stop
the engine and determine the cause.
11.After the hydraulic system starts to show signs of fill,
actuate lift control lever until the lift cylinder rod moves
in and out several times. If the cylinder rod does not
move after 10 to 15 seconds , or the pump emits abnor-
mal sounds, shut the engine off immediately and deter-
mine cause or problem. Inspect for the following:
A. Loose filter or suction lines.
B. Blocked suction line.
C. Faulty charge relief valve.
D. Faulty gear pump.
12.If cylinder does move in 10 to 15 seconds , proceed
to step 13.
13.Operate the traction pedal in the forward and reverse
directions. The wheels off the ground should rotate in
the proper direction.
A. If the wheels rotate in the wrong direction, stop
engine, remove lines from bottom of piston (traction)
pump, and reverse the connections.
B. If the wheels rotate in the proper direction, stop
engine.
14.Adjust traction pedal to the neutral position (see
Traction Unit Operator’s Manual).
15.Check operation of the traction interlock switch (see
Traction Unit Operator’s Manual).
16.Remove blocks from frame and lower machine. Re-
move chocks from remaining wheels.
17.If the piston (traction) pump or a traction motor was
replaced or rebuilt, run the machine so all wheels turn
slowly for 10 minutes.
18.Operate machine by gradually increasing its work
load to full over a 10 minute period.
19.Stop the machine. Check hydraulic reservoir and fill
if necessary. Check hydraulic components for leaks and
tighten any loose connections.