Troubleshooting - Doosan DX140R Shop Manual

Troubleshooting

General Cautions
Here, counter-measures to be taken when troubles have
happened while the motor is in operation are described.
As for general precaution.
1. Consider a cause of the trouble before repairing Before
setting to work, think whether the same thing has
happened before or not.
Also, think again whether it is the motor that is in trouble.
2. Be careful of dust
It is not too much to say that most troubles are ascribed to
dust so measures for dust prevention is taken into
consideration with utmost care in the case of partial
disassembling.
3. Handling part
Pay attention to the handling of parts not to injure them,
especially to moving parts such as pistons, bearing and
valves etc.
4. Pay attention to work the handling of O-ring, gasket Once
seals have been disassembled, they should be replaced
even if damage is not observed.
Investigation Manner of the Motor Body
It is extremely difficult to trace trouble in the hydraulic circuits.
Inspect the following items and investigation whether or not the
fault is caused by the motor.
1. Inspection the oil in casing
Remove the drain plug and inspect the hydraulic oil in the
casing. If a large amount of metallic particles come out with
the oil, you should suspect a failure of internal parts.
2. Presence of abnormal noise
Check whether the motor emits an abnormal noise.
3. Pressure measurement of various points.
Measure pressures at various points and check for faults,
instead of disassembling parts at random.
4. Measurement of drain quantity
A. In the case of locking the swing and adding the
pressure oil to motor, it's normal the drain rate would
be about under 25 (10)lpm
B. In normal swing mode, the drain rate would be under
2 (1)lpm
Where ( ) is TSM72.
Swing Motor
SP001943
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