Komatsu PC210-8, Руководство по ремонту

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UEN00231-03 40 Troubleshooting
2
PC210, 230, 240-8
General information on troubleshooting 1
Points to remember when troubleshooting 1
k
Stop the machine in a level ground, and check that the lock pin, blocks, and parking brake are
securely fitted.
k
When carrying out the operation with two or more workers, keep strictly to the agreed signals,
and do not allow any unauthorized person to come near.
k
If the radiator cap is removed when the engine is hot, hot coolant may spurt out and cause
burns, so wait for the engine to cool down before starting troubleshooting.
k
Be extremely careful not to touch any hot parts or to get caught in any rotating parts.
k
When disconnecting wiring, always disconnect the negative (–) terminal of the battery first.
k
When removing the plug or cap from a location which is under pressure from oil, water, or air,
always release the internal pressure first. When installing measuring equipment, be sure to con-
nect it properly.
The aim of troubleshooting is to pinpoint the basic cause of the failure, to carry out repairs swiftly, and to pre-
vent reoccurrence of the failure.
When carrying out troubleshooting, and important point is of course to understand the structure and function.
However, a short cut to effective troubleshooting is to ask the operator various questions to form some idea
of possible causes of the failure that would produce the reported symptoms.
1. When carrying out troubleshooting, do not
hurry to disassemble the components.
If components are disassembled immediately
any failure occurs:
q
Parts that have no connection with the fail-
ure or other unnecessary parts will be dis-
assembled.
q
It will become impossible to find the cause
of the failure.
It will also cause a waste of man-hours, parts,
or oil or grease, and at the same time, will also
lose the confidence of the user or operator.
For this reason, when carrying out trouble-
shooting, it is necessary to carry out thorough
prior investigation and to carry out trouble-
shooting in accordance with the fixed proce-
dure.
2. Points to ask user or operator
1)
Have any other problems occurred apart
from the problem that has been reported?
2) Was there anything strange about the
machine before the failure occurred?
3) Did the failure occur suddenly, or were
there problems with the machine condition
before this?
4) Under what conditions did the failure
occur?
5) Had any repairs been carried out before
the failure?
When were these repairs carried out?
6) Has the same kind of failure occurred
before?
3. Check before troubleshooting
1)
Check the oil level
2) Check for any external leakage of oil from
the piping or hydraulic equipment.
3) Check the travel of the control levers.
4) Check the stroke of the control valve
spool.
5) Other maintenance items can be checked
externally, so check any item that is con-
sidered to be necessary.
4. Confirming failure
q
Confirm the extent of the failure yourself,
and judge whether to handle it as a real
failure or as a problem with the method of
operation, etc.
a
When operating the machine to re-
enact the troubleshooting symptoms,
do not carry out any investigation or
measurement that may make the
problem worse.
5. Troubleshooting
q
Use the results of the investigation and
inspection in Items 2 – 4 to narrow down
the causes of failure, then use the trouble-
shooting flowchart to locate the position of
the failure exactly.
a
The basic procedure for troubleshoot-
ing is as follows.
1)
Start from the simple points.
2) Start from the most likely points.
3) Investigate other related parts or
information.
6. Measures to remove root cause of failure
q
Even if the failure is repaired, if the root
cause of the failure is not repaired, the
same failure will occur again.
To prevent this, always investigate why
the problem occurred. Then, remove the
root cause.