Service Manual

Procedure for System Relief Pressure Test:
1. Make sure hydraulic oil is at normal operating tem-
perature b
y operating the machine for approximately 10
minutes.
2. Park machine on a level surface, fully raise coring
head, stop engine and remove key from the ignition
switch.
3. Raise lock–up brackets on each side of machine and
lower coring head until it rests on brackets.
4. Read Precautions For Hydraulic Testing in this sec-
tion.
2
1
CAUTION
draulic oil.
Operate all hydraulic controls to relieve system
pressure and avoid injury from pressurized hy-
Figure 12
1. Hydraulic lift cylinder 2. Lift cylinder lower fitting
5. With engine off, move lift control lever to raise and
lower to relieve system pressure.
6. Disconnect hydraulic hose from lower fitting on lift
cylinder (Fig. 12). Install T–fitting with pressure gauge
between d
isconnected hose and lower fitting on lift cylin-
der.
7. Make sure that gear shift lever is in neutral and trac-
tion lever is disengaged.
8. Start engine and operate engine at full speed (3600
+ 100 RPM).
9. Move lift lever to the raise position and while holding
the lift lever in the raised position, watch the pressure
gauge. Record pressure when the relief valve opens.
10.Return lift lever to neutral position. Shut off engine.
11. Relief valve should open at approximately 1300 PSI
(89.6 Bar).
12.If specification is not met, inspect pressure control
valve located in hydraulic pump.
13.Disconnect pressure gauge and T–fitting from hy-
draulic
hose and lift cylinder. Connect hydraulic hose to
lift cylinder.
Hydraulic
System
Greens Aerator Page 4 – 13 Hydraulic System