Troubleshooting
Safety, Operation and Maintenance Manual - Aug 2012
6-39
SY115C9/135C/155H Crawler Hydraulic Excavator
6.10 Other Common Failures
Failure
Causes
Remedy
Structure member
noise loud
●
Loose fastener
●
Bigger clearance between arm and buck-
et end faces due to wear
●
Check and retighten.
●
Reduce the clearance to a value that
is smaller than 1mm.
Bucket tip falls off dur-
ing operation.
●
Spring deformed and weak due to re-
peated use of bucket tip pin
●
Bucket tip pin not matching the adaptor
●
Replace bucket tip pin
Track kinks.
●
Loose track
●
Traveling at high speed on rough road in
the direction of sprocket
●
Tighten the track
●
Travel slowly on rough road in the
direction of idler.
Fan not working
●
Improper electrical connection or con-
nector contact
●
Air
fl
ow control switch, relay or tempera-
ture control switch damaged
●
Fuse exploded or battery voltage low
●
Repair/replace.
Fan running but pro-
ducing less air
fl
ow
●
Air intake side blocked
●
Evaporator or condenser fin plugged,
giving ineffective heat conduction
●
Fan vane seized or damaged
●
Clean/replace.
Compressor not work-
ing or working with dif
fi
-
culty
●
Compressor clutch not picking up due to
wire break or defective contact of electri-
cal circuit
●
Loose compressor belt
●
Wire break or failure of compressor
clutch coil
●
Insuf
fi
cient or excessive refrigerant
●
Repair
●
Adjust the tension of compressor
belt
●
Replace clutch coil
●
Refill/drain the refrigerant to a suit-
able level
Refrigerant insuf
fi
cient
●
Refrigerant leaks.
●
Insuf
fi
cient re
fi
lling
●
Eliminate the leaking point.
●
Re
fi
ll suitable amount of refrigerant.
High/low pressure
reading in normal op-
eration
Ambient temperature
:
30
~
50
℃
High pressure gauge: 1.47
~
1.67MPa
(
15
~
17kgf/cm2
)
Low pressure gauge: 0.13
~
0.20MPa
(
1.4
~
2.11kgf/cm2
)
Low pressure gauge
reads higher
.
Low pressure
tube surface
frosted
●
Expansion valve opening excessively.
●
Defective contact of expansion valve
thermo-bulb
●
Excessive refrigerant in the system
●
Replace expansion valve.
●
Install thermo-bulb correctly.
●
Drain refrigerant to the specified
level.