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HYDRAULIC PRESSURE SETTINGS
CASE TRAINING CENTER
AUGUST 2000
No movement on any function
(Control cancellation lever in the low position)
Lack of power or speed on one of the attachment movements
(No problems with the other movements)
No. Tests Results Repairs
1 Check the hydraulic oil level Lack of hydraulic oil Top up as required
2 Check the pilot pressure at P3 Pressure below 30 bar (3.0 MPa)
Adjust the pilot circuit secondary
relief valve, change it if necessary
3
Check the pilot pressure at outlet
port B on the 6 solenoid valve block
Pressure below 30 bar (3.0 MPa)
Check electrical supply and the
solenoid valve coil (Nos. 4 and 5)
4
Check the voltage at the pilot
solenoid valve connector (blue)
Voltage < 24 V
check the electrical supply and
mechanical adjustment of the
controls cancellation contact switch.
Check the harness between the
contact switch and the solenoid valve
5 Check the pilot solenoid valve coil
Infinite or 0 Ohm Change the solenoid valve
About 40 Ohm Change the solenoid valve coil
No. Tests Results Repairs
1 Check the P1 or P2 pressure Pressure too low
Incident on the secondary relief valve
of the faulty movement, adjust or
change
2
With the engine at full speed (in
mode "H"), and the hydraulic oil at
50°C, check the speed of the
movement concerned
Below:
- Boom raising: 3.4 seconds
- Dipper retracting: 3.6 seconds
- Dipper extending: 2.6 seconds
- Bucket opening: 1.9 seconds
- Bucket closing: 2.4 seconds
Leak at the non-return check valve,
adjust or change
3
With a load on the end of the
attachment and 1 m above the
ground, check the retracting and
extending of the cylinder rods
Rod retracting or extending over
10 mm greater than:
- Boom: 30 mm
- Dipper: 60 mm
- Bucket: 20 mm
Leak at attachment cylinders,
change the piston seals or change
the cylinder
4
Manually check the movement of the
pilot spool in the control valve for the
faulty movement
Difficult to move
Spool stuck or scratched, spring
broken
5
Check the pilot pressure of the
control valve spool
Pressure below 30 bar
Check the operation of the control
lever spool, change or repair
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