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4 - 7
Slew Motor Relief Valve
1
Prepare the machine
Put the operator levers into neutral and lower the gate
lock lever. Start the engine and park the machine on
level ground. Operate the dipper out and lower the
boom to set the bucket on the ground. Lower the blade
onto the ground. Stop the engine. Release the hydraulic
oil tank pressure. (See
Releasing Tank Pressure
).
2
Connect a 0 - 400 bar (0 - 6000 lb/in
2
) pressure gauge
and adaptor to pressure test point
G1
(see view
A
on
page 4 - 1).
Note:
Pressure can also be measured on the upper section
of the slew motor.
3
Initiate slew lock procedures.
a
Press the slew lock switch ON (on the cab left
console) and confirm that the slew lock symbol
appears on the monitor.
b
Start the engine, and operate the engine at around
1000 r.p.m, and operate the slew lever slowly (Slew
Right
A
, Slew Left
B
). Listen to confirm that the
relief valve is heard to operate and check that the
machine does not slew.
c
Run the engine at maximum no-load speed in the
S
mode.
d
Operate the slew lever.
4
The pressure gauge reading should be compared to the
technical data at the start of the section.
5
If the pressure is within the limits, stop engine, release
tank pressure and remove the gauge and adaptor. If the
readings are outside the limits, continue as below.
6
Pressure Adjustment
Repeat step 3 above and confirm pressure setting.
a
On the appropriate slew motor relief valve
(H
for
right slew,
J
for left slew), loosen lock nut
Y
.
b
Adjust screw
Z
(while watching the pressure gauge)
until the correct pressure is achieved.
c
Hold adjusting screw
Z
and tighten locknut
Y
.
d
After locking, check the relief pressure again. If it is
not within the specified limits (see step 4 above)
repeat steps 6a to 6d.
e
Repeat step 5 above.
Section E
Hydraulics
9803/6020
Section E
4 - 7
Issue 1
Pressure Testing
12
SL
MODE
J
J
A
A
B
B
H
H
Z
Y
284430
292490
293300
Summary of Contents for JS70
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Page 189: ...Section E Section E Hydraulics 9803 6020 Issue 1 33 4 33 4 Control Valves Control Valve 291360...