Komatsu 80001 User Manual

SEN04124-00 40 Troubleshooting
6 PC130-8
H-1 Speed or power of all work equipment, swing, and travel are low 1
Trouble • Speed or power of all work equipment, swing, and travel are low.
Related
information
• Conduct the troubleshooting in working mode P.
Possible causes
and standard
value in normal
state
Cause Standard value in normal state/Remarks on troubleshooting
1 Malfunction of unload valve
a Keep the engine stopped for the preparations, and keep it
running at high idle during the troubleshooting.
Control levers Unload pressure
All levers in NEUTRAL
2.8 ± 1.0 MPa
{28 ± 10 kg/cm
2
}
2
Defective adjustment or
operation of main relief valve
(power-up mode)
a Keep the engine stopped for the preparations, and keep it
running at high idle during the troubleshooting.
Control lever Main relief pressure
Arm relieved in IN direction
34.8 MPa
{355 kg/cm
2
}
If the oil pressure cannot be set normally by adjustment, the main
relief valve may be malfunction or may have an internal defect.
Check the main relief valve directly.
3
Malfunction of self-pressure
reducing valve
a Keep the engine stopped for the preparations, and keep it
running at high idle during the troubleshooting.
Control levers Control circuit basic pressure
All levers in NEUTRAL
3.2 ± 0.5 MPa
{33 ± 5 kg/cm
2
}
4
Defective adjustment or
operation of PC valve
a Keep the engine stopped for the preparations, and keep it
running at high idle during the troubleshooting.
Measured oil
pressure
Measurement
conditions
Oil pressure ratio
Pump discharge
pressure
Swing lock: ON
Arm: Relieved in IN
direction
1
PC valve output
pressure
Approx. 0.6
(Approx. 3/5)
If the oil pressure cannot be set normally by adjustment, the PC
valve may be malfunction or may have an internal defect. Check
the PC valve directly.
5
Defective adjustment or
operation of LS valve
Measured oil
pressure
Oil pressure ratio
All levers in
NEUTRAL
Bucket curled
(Lever at stroke end)
Pump discharge
pressure
Almost same
pressure
1
LS valve output
pressure
Approx. 0.6
(Approx. 3/5)
If the oil pressure cannot be set normally by adjustment, the LS
valve may be malfunction or may have an internal defect. Check
the LS valve directly.
6 Malfunction of servo piston The servo piston may have malfunction. Check it directly.
7 Piston pump defective
If there is none of the causes listed above, the piston pump may
have problems of lowering of performance, malfunction, internal
defect, etc.
+2.0
–1.0
+20
–10

Komatsu 80001 Specifications

General

Brand	Komatsu
Model	80001
Category	Excavators
Language	English